Front End Development Libraries

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freeCodeCamp
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Free Certificate
Languages

English
Certificate

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Duration & workload

300 hours
Sessions

On-Demand
Level

Intermediate

Found in

Workshop
Lab
Lecture
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Practice
Warm Up

Syllabus

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Debug Camperbot's Profile Page
What Role Does HTML Play on the Web?
What Are Attributes, and How Do They Work?
Debug a Pet Adoption Page
What Is the Role of the Link Element in HTML, and How Can It Be Used to Link to External Stylesheets?
What Is an HTML Boilerplate, and Why Is It Important?
What Is UTF-8 Character Encoding, and Why Is It Needed?
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Build a Recipe Page
What are Div Elements and When Should You Use Them?
What Are IDs and Classes, and When Should You Use Them?
What Are HTML Entities, and What Are Some Common Examples?
What Is the Role of the Script Element in HTML, and How Can It Be Used to Link to External JavaScript Files?
What Is the Role of the Meta Description, and How Does It Affect SEO?
What Is the Role of Open Graph Tags, and How Do They Affect SEO?
Build a Travel Agency Page
What Are the Roles of the HTML Audio and Video Elements, and How Do They Work?
Build an HTML Audio and Video Player
What Are Common Ways to Optimize Media Assets?
What Are the Different Types of Image Licenses, and How Do They Work?
What Are SVGs, and When Should You Use Them?
What Are Replaced Elements, and What Are Some Examples?
How Do You Embed Videos onto Your Page Using the iframe Element?
Build a Video Compilation Page
What Are the Different Target Attribute Types, and How Do They Work?
What Is the Difference Between Absolute and Relative Paths?
What Is the Difference Between Slashes, a Single Dot, and Double Dot in Path Syntax?
What Are the Different Link States, and Why Are They Important?
Basic HTML Review
Basic HTML Quiz
Why Should You Care About Semantic HTML?
Why is it Important to Have Good Structural Hierarchy?
What Is the Difference Between Presentational and Semantic HTML?
When Should You Use the Emphasis Element Over the Idiomatic Text Element?
When Should You Use the Strong Element Over the Bring Attention To Element?
What Are Description Lists, and When Should You Use Them?
How Do Block and Inline Quotes Work in HTML?
How Do You Display Abbreviations in HTML?
How Do You Display Addresses in HTML?
How Do You Display Times and Dates in HTML?
How Do You Display Mathematical Equations and Chemical Formulas in HTML?
How Do You Represent Computer Code in HTML?
What Are the U, S, and Ruby Elements Used For, and How Do They Work?
Build an Event Hub
Semantic HTML Review
Semantic HTML Quiz
How Do Forms, Labels, and Inputs Work in HTML?
What Are the Different Types of Buttons, and When Should You Use Them?
What Is Client-Side Form Validation in HTML Forms, and What Are Some Examples?
What Are the Different Form States, and Why Are They Important?
What Are HTML Tables Used For, and What Should They Not Be Used For?
Build a Book Catalog Table
What Is an HTML Validator, and How Can It Help You Debug Your Code?
How to Use the DOM Inspector and DevTools to Debug and Build Your Projects
HTML Tables and Forms Review
HTML Tables and Forms Quiz
Build a Survey Form
What Is Accessibility?
What Are Screen Readers, and Who Uses Them?
What Are Large Text or Braille Keyboards, and Who Uses Them?
What Are Alternative Pointing Devices Such as Trackballs, Joysticks, and Touchpads Used For?
What Are Screen Magnifiers Used For?
What Is Voice Recognition Software Used For?
What Are Some Common Accessibility Auditing Tools to Use?
How Does Proper Heading Level Structure Affect Accessibility?
What Are Best Practices for Tables and Accessibility?
Why Is It Important for Inputs to Have an Associated Label?
What Is the Purpose of WAI-ARIA, and How Does It Work?
What Are ARIA Roles?
What Are the Roles of the aria-label and aria-labelledby Attributes?
What Is the aria-hidden Attribute, and How Does It Work?
What Is the aria-describedby Attribute, and How Does It Work?
When Is the alt Attribute Needed, and What Are Some Examples of Good Alt Text?
What Are the Accessibility Benefits for Good Link Text, and What Are Examples of Good Link Text?
What Are Good Ways to Make Audio and Video Content Accessible?
What Are Some Ways to Make Web Applications Keyboard Accessible?
Build a Checkout Page
Design a Movie Review Page
Build a Multimedia Player
HTML Accessibility Review
HTML Accessibility Quiz
HTML Review
What Are the Basic Parts of a Computer?
How Can You Effectively Work With Your Keyboard, Mouse, and Other Pointing Devices?
What Are the Different Types of Internet Service Providers?
What Are Safe Ways to Sign Into Your Computer?
What Are the Different Types of Tools Professional Developers Use?
How Can You Use File Management Applications on Your Computer?
What Are Best Practices for Naming Files for Web Applications?
What Are Best Practices for File/Folder Organization in Web Applications?
How Can You Create, Move, and Delete Files and Folders Using Explorer/Finder?
How Can You Search for Files and Folders on Your Computer?
What Are Some Common File Types You Will Work With in Web Applications?
What Are Some of the Common Web Browsers Available Today and How Do You Install One?
What Is the Difference Between a Web Browser, a Website, and a Search Engine?
How to Use a Search Engine Effectively to Achieve Optimal Results
Computer Basics Review
Computer Basics Quiz
What Is CSS, and What Is Its Role on the Web?
What Is the Basic Anatomy of a CSS Rule?
What Is the Meta Viewport Element Used For?
What Are Some Default Browser Styles Applied to HTML?
What Are Inline, Internal, and External CSS, and When Should You Use Each One?
How Do Width and Height Work?
What Are the Different Types of CSS Combinators?
What Is the Difference Between Inline and Block-Level Elements in CSS?
How Does Inline-Block Work, and How Does It Differ from Inline and Block Elements?
What Are Margins and Padding, and How Do They Work?
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Design a Business Card
What Is CSS Specificity, and the Specificity for Inline, Internal, and External CSS?
What Is the Universal Selector, and What Is Its Specificity?
What Is the Specificity for Type Selectors?
What Is the Specificity for Class Selectors?
What Is the Specificity for ID Selectors?
What Is the important Keyword, and What Are the Best Practices for Using It?
How Does the Cascade Algorithm Work at a High Level?
How Does Inheritance Work with CSS at a High Level?
CSS Fundamentals Review
CSS Fundamentals Quiz
How Do You Space List Items Using margin or line-height?
How Do the Different list-style Properties Work?
Why Are Default Link Styles Important for Usability on the Web?
How Do You Style the Different Link States?
Build a Stylized To-Do list
How Do Background Image Size, Repeat, Position, and Attachment Work?
What Is a Background Gradient, and How Does It Work?
What Are Some Accessibility Considerations for Backgrounds?
What Are the Different Ways You Can Add Borders Around Images?
Design a Blog Post Card
Lists, Links, Background and Borders Review
Lists, Links, Backgrounds and Borders Quiz
What Are Common Design Terms to Help You Communicate with Designers?
How Do You Create Good Background and Foreground Contrast in Your Designs?
What Is the Importance of Good Visual Hierarchy in Design?
How Does Scale Work in Design?
How Does Alignment Work in Design?
What Is the Importance of Whitespace in Design?
What Are Best Practices for Working with Images in Your Designs?
What Is Progressive Enhancement?
What Is User-Centered Design?
What Are User Requirements, User Research, and Testing?
What Are Best Practices for Designing a Dark Mode Feature?
What Are Best Practices for Designing Breadcrumbs?
What Are Best Practices for Designing Cards?
What Are Best Practices for Designing Infinite Scrolls?
What Are Best Practices for Designing Modal Dialogs?
What Are Best Practices for Progress Indication on Forms, Registration, and Setup?
What Are Best Practices for Designing Shopping Carts?
What Is Progressive Disclosure?
What Is Deferred and Lazy Registration?
What Are Design Briefs and How Do Developers Work with Them?
What Are Some Common Tools Developers Should Know About That Are Used by Designers in the Industry?
Design Fundamentals Review
Design Fundamentals Quiz
What Are Absolute Units in CSS, and When Should You Use Them?
What Are Percentages in CSS, and When Should You Use Them?
What Are ems and rems in CSS, and When Should You Use Them?
What Are vh and vw Units, and When Should You Use Them?
What Is the calc() Function, and How Does It Work?
Build an Event Flyer Page
CSS Relative and Absolute Units Review
CSS Relative and Absolute Units Quiz
What Are Pseudo-classes, and How Do They Work?
What Are Examples of Element User Action Pseudo-classes?
What Are Examples of Input Pseudo-classes?
What Are Examples of Location Pseudo-classes?
What Are Examples of Tree-structural Pseudo-classes?
What Are Examples of Functional Pseudo-classes?
What Are Pseudo-elements, and How Do They Work?
Build a Job Application Form
CSS Pseudo-classes Review
CSS Pseudo-classes Quiz
What Is Color Theory in Design?
What Are Named Colors in CSS, and When to Use Them?
What Is the RGB Color Model, and How Does the RGB Function Work in CSS?
What Is the HSL Color Model, and How Does the HSL Function Work in CSS?
What Are Hex Codes, and How Do They Work in CSS?
What Are Linear and Radial Gradients, and How Do They Work in CSS?
Design a Set of Colored Boxes
CSS Colors Review
CSS Colors Quiz
What Are Some Best Practices for Styling Text Inputs?
When Should You Use appearance: none to Deal with Issues Styling Search Inputs and Checkboxes?
What Are Common Issues When Styling Special Input Elements?
Design a Contact Form
Design a Feature Selection Page
Styling Forms Review
Styling Forms Quiz
What Is Overflow in CSS, and How Does It Work?
What Is the CSS Transform Property, and How Does It Work?
What Is the CSS Box Model, and How Does It Work?
What Is Margin Collapsing, and How Does It Work?
What Is the Difference Between content-box and border-box?
What Is a CSS Reset, and What Are Some Common Examples?
What Is the CSS Filter Property, and What Are Common Examples?
Build a Confidential Email Page
CSS Layouts and Effects Review
CSS Layout and Effects Quiz
What Is CSS Flexbox, and When Should You Use It?
What Are Some Common Flex Properties, and How Do They Work?
CSS Flexbox Review
CSS Flexbox Quiz
Build a Page of Playing Cards
What Are the Fundamentals of Typography?
What Are Some Best Practices for Working with Typography in Your Designs?
What Are Font Families and How Do They Work?
What Are Web Safe Fonts?
What Is the @font-face At-Rule, and How Does It Work?
How Do You Work with External Fonts Like Font Squirrel and Google Fonts?
What Is the text-shadow Property, and How Does It Work?
Build a Newspaper Article
CSS Typography Review
CSS Typography Quiz
What Are Some Tools to Check for Good Color Contrast on Sites?
What Are Best Practices for Hiding Content So It Doesn't Become Inaccessible?
Build a Tribute Page
CSS Accessibility Review
CSS Accessibility Quiz
What Are Common Use Cases for Using Floats, and How Do They Work?
What Is Relative Positioning, and How Does This Differ from the Default Static Positioning?
What Is Absolute Positioning, and How Does It Work?
What Is Fixed and Sticky Positioning, and How Does It Differ from Absolute Positioning?
What Is the Z-Index Property, and How Does It Work to Control the Stacking of Positioned Elements?
Build a House Painting
CSS Positioning Review
CSS Positioning Quiz
What Is the Attribute Selector, and How Can It Be Used to Target Links with the href and title Attributes?
How to Use the Attribute Selector to Target Elements with the lang and data-lang Attributes?
How to Use the Attribute Selector to Target Ordered List Elements with the type Attribute?
CSS Attribute Selectors Review
CSS Attribute Selectors Quiz
Build a Book Inventory App
What Is Responsive Web Design, and What Is Its Relationship to Tools Like CSS Grid and Flexbox?
How Do Media Queries Work, and What Are Some Common Media Types and Features?
What Are Media Breakpoints, and What Are Common Breakpoints in Modern Design?
What Is the Mobile First Approach in Responsive Web Design?
Responsive Web Design Review
Responsive Web Design Quiz
Build a Technical Documentation Page
What Are CSS Custom Properties, and How Do They Work?
What Is the @property Rule, and How Does It Work with Fallbacks?
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Build an Availability Table
CSS Variables Review
CSS Variables Quiz
What Is CSS Grid, and How Does It Differ from Flexbox?
How Can You Create Flexible Grids with the fr Unit?
How Can You Create Gaps Between Tracks in a Grid?
How Can You Repeat Track Listings in a Grid Layout?
What Is the Difference Between an Implicit and Explicit Grid?
What Is the minmax() Function and How Does It Work?
How Do the grid-column and grid-row Properties Work?
How Can You Position Items on the Grid Using the grid-template-areas Property?
Design a Newspaper Layout
How Can You Use the DevTools Inspection Tool and CSS Validators to Debug Your CSS?
CSS Grid Review
CSS Grid Quiz
Build a Product Landing Page
What Are CSS Animations, and How Do They Work?
What Are Accessibility Concerns Around Using Animations, and How Can prefers-reduced-motion Help?
Build a Moon Orbit
Build a Personal Portfolio
CSS Animations Review
CSS Animations Quiz
CSS Review
Responsive Web Design Certification Exam
What Is JavaScript, and How Does It Work with HTML and CSS?
What Is a Data Type, and What Are the Different Data Types in JavaScript?
What Are Variables, and What Are Guidelines for Naming JavaScript Variables?
How Do let and const Work Differently When It Comes to Variable Declaration, Assignment, and Reassignment?
What Is a String in JavaScript, and What Is String Immutability?
What Is String Concatenation, and How Can You Concatenate Strings with Variables?
What Is console.log Used For, and How Does It Work?
What Is the Role of Semicolons in JavaScript, and Programming in General?
What Are Comments in JavaScript, and When Should You Use Them?
Build a JavaScript Trivia Bot
Build a Sentence Maker
What Is Dynamic Typing in JavaScript, and How Does It Differ from Statically Typed Languages?
How Does the typeof Operator Work, and What Is the typeof null Bug in JavaScript?
JavaScript Variables and Data Types Review
JavaScript Variables and Data Types Quiz
What Is Bracket Notation, and How Do You Access Characters from a String?
How Do You Create a Newline in Strings and Escape Strings?
What Are Template Literals, and What Is String Interpolation?
How Can You Find the Position of a Substring in a String?
What Is the prompt() Method, and How Does It Work?
What Is ASCII, and How Does It Work with charCodeAt() and fromCharCode()?
How Can You Test if a String Contains a Substring?
How Can You Extract a Substring from a String?
How Can You Change the Casing for a String?
How Can You Trim Whitespace from a String?
How Can You Replace Parts of a String with Another?
How Can You Repeat a String x Number of Times?
JavaScript Strings Review
JavaScript Strings Quiz
What Is the Number Type in JavaScript, and What Are the Different Types of Numbers Available?
What Are the Different Arithmetic Operators in JavaScript?
What Happens When You Try to Do Calculations with Numbers and Strings?
Debug Type Coercion Errors in a Buggy App
How Does Operator Precedence Work?
How Do the Increment and Decrement Operators Work?
What Are Compound Assignment Operators in JavaScript, and How Do They Work?
Debug Increment and Decrement Operator Errors in a Buggy App
What Are Booleans, and How Do They Work with Equality and Inequality Operators?
What Are Comparison Operators, and How Do They Work?
What Are Unary Operators, and How Do They Work?
What Are Bitwise Operators, and How Do They Work?
What Are Conditional Statements, and How Do If/Else If/Else Statements Work?
What Are Binary Logical Operators, and How Do They Work?
What Is the Math Object in JavaScript, and What Are Some Common Methods?
Build a Fortune Teller
How Does isNaN Work?
How Do the parseFloat() and parseInt() Methods Work?
What Is the toFixed() Method, and How Does It Work?
JavaScript Math Review
JavaScript Math Quiz
How Do Comparisons Work with Null and Undefined Data Types?
What Are Switch Statements and How Do They Differ from If/Else Chains?
JavaScript Comparisons and Conditionals Review
JavaScript Comparisons and Conditionals Quiz
What Is the Purpose of Functions, and How Do They Work?
What Are Arrow Functions, and How Do They Work?
What Is Scope in Programming, and How Does Global, Local, and Block Scope Work?
Build a Boolean Check Function
Build an Email Masker
Build a Celsius to Fahrenheit Converter
Build a Card Counting Assistant
Build a Leap Year Calculator
Implement the Truncate a String Algorithm
Build a Confirm the Ending Tool
JavaScript Functions Review
JavaScript Functions Quiz
What Are the Key Characteristics of JavaScript Arrays?
How Do You Access and Update Elements in an Array?
How Do You Add and Remove Elements from the Beginning and End of an Array?
What Is the Difference Between One-Dimensional and Two-Dimensional Arrays?
What Is Array Destructuring, and How Does It Work?
How Can You Use String and Array Methods to Reverse a String?
Build a Lunch Picker Program
Build a Golf Score Translator
How Do You Get the Index for an Element in an Array Using the indexOf Method?
How Do You Add and Remove Elements from the Middle of an Array?
How Can You Check if an Array Contains a Certain Value?
What Is a Shallow Copy of an Array, and What Are Some Ways to Create These Copies?
JavaScript Arrays Review
JavaScript Arrays Quiz
What Is an Object in JavaScript, and How Can You Access Properties from an Object?
How Can You Remove Properties from an Object?
How to Check If an Object Has a Property?
How Do You Work with Accessing Properties from Nested Objects and Arrays in Objects?
What Is the Difference Between Primitive and Non-Primitive Data Types?
What Is the Difference Between Functions and Object Methods?
What Is the Object() Constructor, and When Should You Use It?
What Is JSON, and How Do You Access Values Using Bracket and Dot Notation?
How Do JSON.parse() and JSON.stringify() Work?
What Is the Optional Chaining Operator, and How Does It Work?
What Is Object Destructuring, and How Does It Work?
Build a Quiz Game
Build a Record Collection
JavaScript Objects Review
JavaScript Objects Quiz
How Do Loops and Iteration Work in JavaScript?
How Does the For...of Loop Work, and When Should You Use It?
What Is the For...in Loop, and When Should You Use It?
What Is a While Loop, and How Does It Differ from the Do...while Loop?
What Are the Break and Continue Statements Used for in Loops?
Build a Longest Word Finder App
Build a Factorial Calculator
Implement the Mutations Algorithm
Implement the Chunky Monkey Algorithm
Build a Profile Lookup
Build a String Repeating Function
Build a Missing Letter Detector
JavaScript Loops Review
JavaScript Loops Quiz
What Is a String Object, and How Does It Differ from String Primitive?
What Is the toString() Method, and How Does It Work?
What Is the Number Constructor, and How Does It Work for Type Coercion?
What Are Some Common Practices for Naming Variables and Functions?
How Do You Get the Length for an Array, and How Can You Create an Empty Array of Fixed Length?
What Are Linters and Formatters, and How Can They Help You with Code Consistency?
What Is Memory Management, and How Does It Work in JavaScript?
What Are Closures, and How Do They Work?
Build a String Inverter
Build the Largest Number Finder
Build a First Element Finder
Implement the Slice and Splice Algorithm
Build a Pyramid Generator
Build a Gradebook App
What Is the var Keyword, and Why Is It No Longer Suggested to Use It?
What Is Hoisting?
Build a Title Case Converter
Implement a Falsy Remover
Build an Inventory Management Program
What Is a Module in JavaScript, and How Can You Import and Export Modules in Your Program?
What is the arguments Object?
What are Rest Parameters and How Do They Differ from the arguments Object?
Implement a Unique Sorted Union
Build a Password Generator App
Design a Sum All Numbers Algorithm
Implement a DNA Pair Generator
Implement an HTML Entity Converter
Build an Odd Fibonacci Sum Calculator
Implement an Element Skipper
JavaScript Fundamentals Review
JavaScript Fundamentals Quiz
What Is a Callback Function, and How Does It Work with the forEach Method?
What Are Higher-Order Functions?
What Is the Map Method, and How Does It Work?
What Is the Filter Method, and How Does It Work?
What Is the Reduce Method, and How Does It Work?
What Is Method Chaining, and How Does It Work?
How Does the Sort Method Work?
How Do the every() and some() Methods Work?
Build a Book Organizer
Implement a Sorted Index Finder
Build a Symmetric Difference Function
Implement a Value Remover Function
Implement a Matching Object Filter
Build a Prime Number Sum Calculator
Implement a Range-Based LCM Calculator
Create a Deep Flattening Tool
Build an All-True Property Validator
JavaScript Higher Order Functions Review
JavaScript Higher Order Functions Quiz
What Is an API, and What Are Web APIs?
What Is the DOM, and How Do You Access Elements?
How Do DOM Nodes Exist Relative to Each Other in the DOM Tree?
What Is the querySelectorAll() Method, and When Should You Use It?
How Do You Create New Nodes Using innerHTML and createElement()?
What Is the Difference Between innerText, textContent, and innerHTML?
How Do You Add and Remove Nodes from the DOM with appendChild() and removeChild()?
How Do the Navigator, Window, and Document Work?
How Do You Add Attributes with setAttribute()?
What Is the Event Object?
How Does the addEventListener Method Work?
How Does the removeEventListener Method Work?
What Are Inline Event Handlers, and Why Is It Best Practice to Use addEventListener Instead?
How Do You Manipulate Styles Using Element.style and Element.classList?
What Is the DOMContentLoaded Event, and How Does It Work?
How Do the setTimeout and setInterval Methods Work?
What Is the requestAnimationFrame() API, and How Can It Be Used to Set Up an Animation Loop?
What Is the Web Animations API, and How Does It Relate to CSS Animation Properties?
What Is the Canvas API, and How Does It Work?
How Do You Open and Close Dialog Elements Using JavaScript?
Build a Favorite Icon Toggler
What Is the Change Event, and How Does It Work?
How Do Event Bubbling, and Event Delegation Work?
Build a Real Time Counter
Build a Lightbox Viewer
Build a Set of Football Team Cards
DOM Manipulation and Click Events with JavaScript Review
DOM Manipulation and Click Events with JavaScript Quiz
How Do You Make Dynamic and Interactive Content Accessible?
What Is the aria-expanded Attribute, and How Does It Work?
What Is the aria-live Attribute, and How Does It Work?
What Are Some Common ARIA States Used on Custom Control Elements?
What Is the aria-controls Attribute, and How Does It Work?
Build a Theme Switcher
JavaScript and Accessibility Review
JavaScript and Accessibility Quiz
What Are Some Examples of Common JavaScript Errors?
How Does the Throw Statement Work?
How Does try...catch...finally Work?
How Does the Debugger Statement Work?
What Are Some Examples of Using Advanced JavaScript Debugging Techniques?
Debug a Random Background Color Changer
Debugging JavaScript Review
Debugging JavaScript Quiz
What Are Regular Expressions, and What Are Some Common Methods?
What Are Some Common Regular Expression Modifiers Used for Searching?
How Can You Match and Replace All Occurrences in a String?
What Are Character Classes, and What Are Some Common Examples?
What Are Lookahead and Lookbehind Assertions, and How Do They Work?
What Are Regex Quantifiers, and How Do They Work?
What Are Capturing Groups and Backreferences, and How Do They Work?
Build a Palindrome Checker
Build a RegEx Sandbox
Implement a Spinal Case Converter
Implement a Pig Latin Translator
Build a Smart Word Replacement Function
JavaScript Regular Expressions Review
JavaScript Regular Expressions Quiz
Build a Markdown to HTML Converter
What Are Some Ways to Validate Forms Using JavaScript?
What Is the Purpose of the preventDefault() Method?
How Does the Submit Event Work with Forms?
Build a Customer Complaint Form
Form Validation with JavaScript Review
Form Validation with JavaScript Quiz
How Does the JavaScript Date Object Work, and What Are Some Common Methods?
What Are the Different Ways to Format Dates?
Build a Date Conversion Program
JavaScript Dates Review
JavaScript Dates Quiz
How Does the Audio Constructor Work, and What Are Some Common Methods?
What Are the Different Types of Video and Audio Formats?
What Are Codecs and How Do They Work?
What Is the HTMLMediaElement API and How Does It Work?
How Can You Work with the Media Streams to Capture Video and Audio from a Local Device?
What Are Some Other Examples of Video and Audio APIs?
JavaScript Audio and Video Review
JavaScript Audio and Video Quiz
Build a Drum Machine
What Are Sets in JavaScript, and How Does It Differ from WeakSets?
What Is the Map Object, and How Does It Differ from WeakMaps?
JavaScript Maps and Sets Review
JavaScript Maps and Sets Quiz
Build a Voting System
What Does CRUD Stand For, and How Do the Basic Operations Work?
What Is localStorage, and What Are Some Common Methods?
What Is sessionStorage, and What Are Some Common Methods?
What Are Cookies, and How Do They Work?
What Is the Cache API, and How Does It Work?
What Are Some Negative Patterns Associated with Client-Side Storage?
How Can You Use Cookies to Store Arbitrary Data, Normally Controlled by HTTP Headers?
What Is IndexedDB, and How Does It Work?
What Are Cache and Service Workers, and How Do They Work?
Build a Bookmark Manager App
Local Storage and CRUD Review
Local Storage and CRUD Quiz
What Are Classes, and How Do They Work in JavaScript?
How Does the This Keyword Work?
What Is Class Inheritance, and How Does It Work?
What Are Static Properties and Methods in Classes?
Build a Project Idea Board
JavaScript Classes Review
JavaScript Classes Quiz
Build a Bank Account Management Program
What Is Recursion, and How Does It Work?
Build a Permutation Generator
Recursion Review
Recursion Quiz
What Is Functional Programming?
What Is Currying, and How Does It Work?
Build an Optional Arguments Sum Function
Build a Sorting Visualizer
JavaScript Functional Programming Review
JavaScript Functional Programming Quiz
What Is Asynchronous JavaScript, and How Does It Differ from Synchronous JavaScript?
How Does the Async Attribute Work Inside Script Elements, and How Does It Differ from the Defer Attribute?
What Is the Fetch API, and What Are Common Types of Resources That Are Fetched from the Network?
How Does the Fetch API Work with Common HTTP Methods and res.json()?
What Are Promises, and How Does Promise Chaining Work?
What Is Async/Await, and How Does It Work?
How Does the JavaScript Engine Work, and What Is a JavaScript Runtime?
What Is the Geolocation API, and How Does the getCurrentPosition Work?
Build an fCC Forum Leaderboard
Asynchronous JavaScript Review
Asynchronous JavaScript Quiz
Build a Weather App
JavaScript Review
JavaScript Certification Exam
What Is the Role of JS Libraries and Frameworks, and Why Are They Used in the Industry?
What Are Single Page Applications, and What Are Some Issues Surrounding Them?
What Is React, and What Is It Commonly Used For?
What Are Components in React, and How Do They Work?
How Can You Import and Export Components in React?
What is Vite, and How Can It Be Used to Set Up a New React Project?
Build a Reusable Footer
How Do You Pass Props from a Parent Component to a Child Component in React?
How Does Conditional Rendering Work in React Components?
How Do You Render Lists in React?
How Do Inline Styles Work in React?
Build a Mood Board
React Basics Review
React Basics Quiz
How Do Events Work in React?
What is State, and How Does the useState Hook Work?
What Is Rendering in React, and How Are Components Displayed on the Screen?
How Do You Update Objects in State?
How Do You Update Arrays in State?
Build a Color Picker App
How Do You Reference Values Using Refs?
What Are Effects in React, and How Does the useEffect Hook Work?
How Can You Create Custom Hooks in React?
Build a One-Time Password Generator
React State and Hooks Review
React State and Hooks Quiz
How Do Forms Work in React?
What Is the useActionState Hook, and How Does It Work?
Build an Event RSVP
How Does Data Fetching Work in React?
What Is the useOptimistic Hook, and How Does It Work?
What Is Memoization, and How Does the useMemo Hook Work?
How Do the useCallback Hook and React.memo Work?
What Is Dependency Management, and How Does It Work with Libraries Like React?
How Does Routing Work in React?
What Are React Frameworks, and Why Are They Commonly Used in the Industry?
What Is Prop Drilling?
What Are State Management Libraries, and When Should You Use Them?
How Can You Debug Your React Components Using the React DevTools?
What Are React Server Components, and How Do They Work?
React Forms, Data Fetching and Routing Review
React Forms, Data Fetching and Routing Quiz
Build a Currency Converter
Build a Tic-Tac-Toe Game
What Is the Difference Between Real Performance and Perceived Performance?
What Are the Key Performance Concepts?
What Is INP?
How to Measure and Improve INP?
How Does a Browser Render a Page?
How Does Performance Impact Sustainability?
What Are Some Ways to Reduce Page Loading Times?
How Do You Improve "Time to Usable"?
How to Improve the Perceived Performance of Features?
What Are Some Key Metrics for Measuring Performance?
What Are Some Common Performance Measurement Tools?
How Can You Use Performance Web APIs to Create Your Own Performance Measurement Tools?
What Are Some Techniques for Improving CSS Performance?
What Are Some Techniques for Improving JavaScript Performance?
Web Performance Review
Web Performance Quiz
What Is the Overall Purpose of Testing Your Applications?
What Is the Software Development Life Cycle, and How Does It Relate to Testing?
What Is Unit Testing?
What Are BDD and TDD?
How Do Assertions Work in Unit Testing?
What Are the Differences Between Mocking, Faking, and Stubbing?
What Is Functional Testing, and How Does It Differ from Unit Testing?
What Is End-to-End Testing?
What Is Usability Testing, and What Does the Process Look Like?
What Is Compatibility Testing?
What Is Performance Testing?
What Is Security Testing?
What Is A/B Testing?
What Is Alpha and Beta Testing?
What Is Regression Testing?
Testing Review
Testing Quiz
What Is a CSS Framework, and What Are Some Advantages and Disadvantages of Using It?
What Is the Value of Using a CSS Preprocessor, and What Are Some Disadvantages?
Build a Music Shopping Cart Page
Design a Photography Exhibit
CSS Libraries and Frameworks Review
CSS Libraries and Frameworks Quiz
What Is Python and What Are Some Common Uses in the Industry?
How Do You Install, Configure and Use Python in Your Local Environment?
How Do You Declare Variables and What Are Naming Conventions to Name Variables?
How Does the Print Function Work?
What Are Common Data Types in Python and How Do You Get the Type of a Variable?
How Do You Work With Strings?
What Are Some Common String Methods?
How Do You Work With Integers and Floating Point Numbers?
How Do Augmented Assignments Work?
How Do Functions Work in Python?
What Is Scope in Python and How Does It Work?
How Do Conditional Statements and Logical Operators Work?
What Are Truthy and Falsy Values, and How Do Boolean Operators and Short-Circuiting Work?
Build an RPG Character
Python Basics Review
Python Basics Quiz
What Are Lists and How Do They Work?
What Are Some Common Methods Used for Lists?
What Are Tuples and How Do They Work?
What Are Some Common Methods for Tuples?
How Do Loops Work?
What Are Ranges and How Can You Use Them in a Loop?
What Are the Enumerate and Zip Functions and How Do They Work?
What Are List Comprehensions and What Are Some Useful Functions to Work With Lists?
What Are Lambda Functions and How Do They Work?
Build a Number Pattern Generator
Loops and Sequences Review
Loops and Sequences Quiz
What Are Dictionaries, and How Do They Work?
What Are Some Common Techniques to Loop Over a Dictionary?
What Are Sets, and How Do They Work?
What Is the Python Standard Library, and How Do You Import a Module?
Dictionaries and Sets Review
Dictionaries and Sets Quiz
Build a User Configuration Manager
What Are Some Common Error Messages in Python?
What Are Some Good Debugging Techniques in Python?
How Does Exception Handling Work?
What Is the Raise Statement and How Does It Work?
Debug an ISBN Validator
Error Handling Review
Error Handling Quiz
How Do Classes Work and How Do They Differ From Objects?
What Are Methods and Attributes, and How Do They Work?
What Are Special Methods and What Are They Used For?
How to Handle Object Attributes Dynamically?
Build a Planet Class
Classes and Objects Review
Classes and Objects Quiz
Build a Budget App
What is Object-Oriented Programming, and How Does Encapsulation Work?
What are Getters and Setters
Build a Game Character Stats Tracker
What Is Inheritance and How Does It Promote Code Reuse?
What Is Polymorphism and How Does It Promote Code Reuse?
What is Name Mangling and How Does it Work?
What Is Abstraction and How Does It Help Keep Complex Systems Organized?
Build a Player Interface
Object Oriented Programming Review
Object Oriented Programming Quiz
Build a Polygon Area Calculator
What Is an Algorithm and How Does Big O Notation Work?
What Are Good Problem-Solving Techniques and Ways to Approach Algorithmic Challenges?
How Do Dynamic Arrays Differ From Static Arrays?
How Do Stacks and Queues Work?
How Do Singly Linked Lists Work and How Do They Differ From Doubly Linked List?
How Do Maps, Hash Maps and Sets Work?
Data Structures Review
Data Structures Quiz
Build a Hash Table
What Is Binary Search and How Does It Differ From Linear Search?
What Is Divide and Conquer, and How Does Merge Sort Work?
Implement the Bisection Method
Implement the Quicksort Algorithm
Implement the Selection Sort Algorithm
Implement the Luhn Algorithm
Searching and Sorting Algorithms Review
Searching and Sorting Algorithms Quiz
Implement the Tower of Hanoi Algorithm
What Are Graphs in Computer Science?
How Do Depth First and Breadth First Search Work?
How Do Matrices and Adjacency Lists Work?
What Are Trees and Tries and How Do They Work?
How Do Priority Queues and Heaps Work?
Build an Adjacency List to Matrix Converter
Implement the Depth-First Search Algorithm
Implement the N-Queens Algorithm
Graphs and Trees Review
Graphs and Trees Quiz
What Is Dynamic Programming and What Are Some Common Algorithms?
Build an Nth Fibonacci Number Calculator
Dynamic Programming Review
Dynamic Programming Quiz
Python Review
Python Certification Exam
What Is a Code Editor and IDE?
How to Install Visual Studio Code onto Your Computer
How to Create a Project and Run Your Code Locally in VS Code
What Are Several Useful Keyboard Shortcuts for Maximizing Productivity in VS Code?
What Are Some Good VS Code Extensions You Can Use in Your Editor?
What Is the Terminal, and How Does It Differ from the Command Line?
What Are Some Shortcuts You Can Use in the Command Line to Speed Up Productivity?
What Is Bash, and What Are Some Basic Commands?
What Are Some Command Options and Flags?
Build a Boilerplate
Bash Commands Review
Bash Commands Quiz
What Are Relational Databases, and How Do They Differ from Non-Relational Databases?
What Are Some Common Relational Databases, and How Do You Install and Use Postgres?
What Is SQL, and How Can You Create a Database with Tables?
What Are the Basic Data Types in SQL?
How Do You Insert and View Data in a Table?
What Are Primary and Foreign Keys in SQL, and How Do They Work?
What Are the Different Types of Relationships in a Relational Database?
What Are the Different Ways to Join Tables?
Build a Database of Video Game Characters
SQL and PostgreSQL Review
SQL and PostgreSQL Quiz
Build a Celestial Bodies Database
What Is Bash Scripting, and What Are Some Advantages to Using It?
Build Five Programs
Bash Scripting Review
Bash Scripting Quiz
What Is Normalization in SQL?
What Is SQL Injection, and What Are Some Ways to Prevent It?
What Is the N+1 Problem?
Build a Student Database: Part 1
Build a Student Database: Part 2
Build a Kitty Ipsum Translator
Build a Bike Rental Shop
Bash and SQL Review
Bash and SQL Quiz
Build a World Cup Database
Build a Salon Appointment Scheduler
What Is Nano?
Build a Castle
What Is Version Control, and Why Are These Systems Necessary?
What Is the Purpose of Sites Like GitHub and GitLab, and What Are Some Benefits of Using Them?
How Do You Install and Set Up Git?
What Is a Repository, and How Do You Create One?
How Do You Handle Security Requirements Like SSH and GPG Keys?
How Do You Push a Local Repository to GitHub?
How Do You Contribute to Other People's Repositories?
How Do You Create a New Branch for Your Repository?
What Is a Pull Request, and How Do You Create One?
What Does a Typical Code Review Process Look Like for Projects?
How Do You Use GitHub Pages to Deploy a Project?
What Are Good Practices for Remaining in Sync with Your Remote Counterparts?
What Is a .gitignore File, and What Are Some Items That Should Be Included Inside It?
What Are Some Best Practices for Developing a Git Branching Strategy?
What Are Merge Conflicts, and How Can You Resolve Them?
What Is CI/CD, and How Does CI Work with GitHub Actions?
Build an SQL Reference Object
Git Review
Git Quiz
Build a Periodic Table Database
Build a Number Guessing Game
Relational Databases Review
Relational Databases Certification Exam
Dialogue 1: Maria Introduces Herself to Tom
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Dialogue 2: Tom Meets the Coworker Next to Him
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Dialogue 3: Tom and Sophie Take a Lunch Break
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Dialogue 4: Sophie Introduces Brian to Tom
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Dialogue 5: End of the First Day
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Dialogue 1: A Mobile Developer Joins the Team
Dialogue 2: Introducing the New Junior Developer
Dialogue 3: Team Meeting Introduction
Dialogue 4: A Training Session
Dialogue 5: Meeting a Client
Dialogue 1: Small Talk
Dialogue 2: New Hobbies
Dialogue 3: Tom Asks About the Team Lead
Dialogue 4: Talking About the Monday Meetings
Dialogue 5: Knowing the Area Around the Company
Dialogue 1: Tom Asks Sophie About Her Routine
Dialogue 2: Anna from HR Tells Tom about the Company Routine
Dialogue 3: Jake Tells Sophie about His Routine
Dialogue 4: James Explains Compliance
Dialogue 5: Brian Asks Sarah about Her Routine as a QA Tester
Dialogue 1: Learn How to Discuss your Morning or Evening Routine
Dialogue 2: Consulting a Wellness Expert
Dialogue 3: Evening Routine with Kids
Dialogue 4: Brian and Maria Talk about Eventful Evenings
Dialogue 5: Sophie and Brian Talk about the Weekend
Dialogue 1: Sophie and James Discuss Their Projects
Dialogue 2: Data Analysis Team Discuss Their Projects
Dialogue 3: Maria and Mark Talk about Their Projects
Dialogue 4: Brian Talks to Amy about Their Projects
Dialogue 5: Bob and Sarah Talk about Their Projects
Dialogue 1: A Job Interview
Dialogue 2: Another Job Interview
Dialogue 3: Two Workmates Talk about Their Backgrounds
Dialogue 4: A Developer with a Different Background
Dialogue 5: Anna Talks About her Experience
Dialogue 1: An Interest in Photography
Dialogue 2: The Bike Rider
Dialogue 3: The Collector
Dialogue 4: Inviting to a Convention
Dialogue 5: Getting into Extreme Sports
Dialogue 1: Describing Other People and What They Do
Dialogue 2: Talking about Anna
Dialogue 3: Talking about Jeff
Dialogue 4: Sophie Asks Bob about His Responsibilities
Dialogue 5: Brian And Sophie Talk about Responsibilities
Dialogue 1: What Motivates the Team?
Dialogue 2: Asking How Someone Feels
Dialogue 3: Talking about Motivations to Pursue a Career
Dialogue 4: Chatting About Gadgets
Dialogue 5: Discussing Open-source Software
Dialogue 1: Talking about Artificial Intelligence
Dialogue 2: Talking about Remote Work and Collaboration Tools
Dialogue 3: Talking about Quantum Computing
Dialogue 4: Talking about Biometrics
Dialogue 5: Talking about Augmented Reality
Dialogue 1: Describing a Workmate
Dialogue 2: Looking for Tom
Dialogue 3: A Guessing Game
Dialogue 4: Checking the Project Details
Dialogue 5: Arrangements for a Company Party
Dialogue 1: Discussing Basic Programming
Dialogue 2: Discussing Debugging
Dialogue 3: Talking about OOP
Dialogue 1: Asking about Data Types
Dialogue 2: Asking about Functions
Dialogue 3: Getting Help with Variables
Dialogue 1: Discussing Low-Code Development
Dialogue 2: Discussing Serverless Computing
Dialogue 3: Discussing AI in Programming
Dialogue 1: Discussing Issues on GitHub
Dialogue 2: Talking about Pull Requests
Dialogue 3: Talking about Debugging
Dialogue 1: Offering Suggestions in a Meeting
Dialogue 2: Asking and Offering Help on a Meeting
Dialogue 3: Improvement Suggestions
Dialogue 1: Asking for Help to Understand Code
Dialogue 2: Asking for Help on a Bug
Dialogue 3: Asking for Peer Reviewing
Dialogue 1: Introduction to Code Documentation
Dialogue 2: Adding Comments to Code
Dialogue 3: Version Control and Documenting Changes
Dialogue 1: Navigating Documentation
Dialogue 2: Understanding Function Descriptions
Dialogue 3: Understanding Parameters and Options
Dialogue 1: Analyzing API Documentation
Dialogue 2: Analyzing Code Documentation for Functions
Dialogue 3: Analyzing Code Documentation for Classes and Objects
Dialogue 1: During a Weekly Meeting
Dialogue 2: A Manager and a Direct Report in a Performance Review
Dialogue 3: Sharing Accomplishments over Lunch
Dialogue 1: Discussing Plans for the Next Project
Dialogue 2: Discussing Strategies for the Release of a Product at a Conference Call
Dialogue 3: Plans for a Presentation
Dialogue 1: Reviewing an App Design
Dialogue 2: What to Prioritize Next
Dialogue 3: How to Approach the Project
Dialogue 1: A Code Review Session
Dialogue 2: Tom's Onboarding with Maria
Dialogue 3: Collaborating on a Bug Fix
Dialogue 1: Solving Coding Challenges
Dialogue 2: Learning a New Technology
Dialogue 3: Offering Assistance and Receiving Guidance
Dialogue 1: An Issue with the Computer
Dialogue 2: An Online Meeting for Software Training
Dialogue 3: Integrating a Framework
A2 English for Developers Certification Exam
Dialogue 1: Hackathon Plans
Dialogue 2: Cybersecurity Training
Dialogue 3: Struggling with IDEs
Dialogue 1: A Debugging Session Recap
Dialogue 2: Project Post-Mortem
Dialogue 3: Tech Conference Experience
Dialogue 1: The Latest User Feedback
Dialogue 2: Post-Development Review
Dialogue 3: Progress and Change
Dialogue 1: Improving Screen Reader Compatibility
Dialogue 2: Closed Captioning Challenges
Dialogue 3: Voice Command Features
Dialogue 4: Accessibility Training for Developers
Dialogue 1: Scheduled Maintenance to Prevent DoS Attacks
Dialogue 2: Responding to Phishing Threats
Dialogue 3: Planning for SQL Injection Prevention
Dialogue 2: Troubleshooting Authentication Errors
Dialogue 3: Preventing MitM attacks
Dialogue 1: If It Doesn't Boot
Dialogue 2: Data Backup
Dialogue 3: What If...
Dialogue 1: Performance Review Feedback
Dialogue 2: Team Feedback Session
Dialogue 3: Client Feedback
Dialogue 1: Choosing a Programming Language
Dialogue 2: Deciding on a Development Environment
Dialogue 3: Selecting a Cloud Platform
Dialogue 1: Project Planning
Dialogue 2: Code Review
Dialogue 1: Balancing Priorities
Dialogue 2: In Person x Remote
Dialogue 3: Split the Stipend
Dialogue 1: Project Timeline Discussion
Dialogue 2: Team Meeting Follow-Up
Dialogue 3: Team Tension Discussion
Dialogue 1: Comparing Software Features
Dialogue 2: Comparing Tech Companies
Dialogue 3: Deciding on the Best Solution
Dialogue 1: Security Protocols Compliance
Dialogue 2: Software Development Outcomes
Dialogue 3: Security Breach Investigation
Dialogue 1: Picking Up Where We Left Off
Dialogue 2: Polite Interruption in a Meeting
Dialogue 3: Project Check-In
Dialogue 1: Guessing the Meaning
Dialogue 2: Flickering Glitches
Dialogue 3: A Misunderstanding With A Client
Dialogue 1: Should Have Noticed That
Dialogue 2: Speculating on a Security Breach
Dialogue 3: Improving Technical Training
Dialogue 1: Optimizing Daily Huddle Meetings
Dialogue 2: Testing the New Chat Feature
Dialogue 3: Evaluating Marketing Impact
Dialogue 1: Negotiating Inventory Needs
Dialogue 2: Rehearsing Pitch
Dialogue 3: Comparing Two Versions of Software
Dialogue 1: Choosing the Right Cloud Storage Solution
Dialogue 2: Who Will Do What
Dialogue 3: Balancing Projects
Dialogue 1: Security Incident Debrief
Dialogue 2: Website Redesign Feedback
Dialogue 3: A System Failure
Dialogue 1: Office Relocation
Dialogue 2: Planning Ahead
Dialogue 3: A New Workstation
Dialogue 1: Milestone Planning
Dialogue 2: Budget Breakdown
Dialogue 3: Inventory Check
Dialogue 1: Reviewing HR Policies
Dialogue 2: Interface Security Review
Dialogue 3: Webinar Coordination
B1 English for Developers Certification Exam
Why Learn Spanish?
How the Certification Works
How to Set Up the Spanish Keyboard on Your Computer
How to Set Up the Spanish Keyboard on Mobile
Spanish Alphabet General Review
Spanish Alphabet Pronunciation Review
Spanish Numbers Pronunciation Review
The Spanish Alphabet Quiz
Grammar Highlights
Glossary
Greetings and Farewells Quiz
Introducing Yourself Quiz
First Questions Quiz
Numbers 10 to 29 General Review
Numbers 10 to 29 Pronunciation Review
Numbers 10 to 29 Quiz
HTML Foundations Lesson A
HTML Foundations Lesson B
HTML Foundations Lesson C
HTML Foundations Lesson D
HTML Foundations Lesson E
HTML Foundations Lesson F
HTML Foundations Lesson G
HTML Foundations Lesson H
Working With Text Lesson A
Working With Text Lesson B
Working With Text Lesson C
Working With Text Lesson D
Working With Text Lesson E
Working With Text Lesson F
Working With Text Lesson G
Working With Text Lesson H
Working With Text Lesson I
Working With Text Lesson J
Links and Images Lesson A
Links and Images Lesson B
Links and Images Lesson C
Links and Images Lesson D
Links and Images Lesson E
Links and Images Lesson F
Links and Images Lesson G
Links and Images Lesson H
Build a Recipe Page Project
CSS Foundations Lesson A
CSS Foundations Lesson B
CSS Foundations Lesson C
CSS Foundations Lesson D
CSS Foundations Lesson E
CSS Foundations Lesson F
CSS Foundations Lesson G
CSS Foundations Lesson H
CSS Foundations Exercise A
CSS Foundations Exercise B
CSS Foundations Exercise C
CSS Foundations Exercise D
CSS Foundations Exercise E
The Cascade of CSS Lesson A
The Cascade of CSS Lesson B
The Cascade of CSS Lesson C
The Cascade of CSS Lesson D
The Cascade of CSS Lesson E
The Cascade of CSS Lesson F
The Cascade of CSS Lesson G
The Cascade of CSS Lesson H
The Box Model Lesson A
The Box Model Lesson B
The Box Model Lesson C
The Box Model Lesson D
The Box Model Lesson E
The Box Model Lesson F
The Box Model Lesson G
The Box Model Lesson H
The Box Model Lesson I
The Box Model Lesson J
The Box Model Lesson K
The Box Model Lesson L
The Box Model Lesson M
Learn Block and Inline Lesson A
Learn Block and Inline Lesson B
Learn Block and Inline Lesson C
Learn Block and Inline Lesson D
Learn Block and Inline Lesson E
Learn Block and Inline Lesson F
Learn Block and Inline Lesson G
Learn Block and Inline Lesson H
Learn Block and Inline Lesson I
Learn Block and Inline Lesson J
Learn Block and Inline Lesson K
Introduction to Flexbox Lesson A
Introduction to Flexbox Lesson B
Introduction to Flexbox Lesson C
Introduction to Flexbox Lesson D
Introduction to Flexbox Lesson E
Introduction to Flexbox Lesson F
Introduction to Flexbox Lesson G
Introduction to Flexbox Lesson H
Introduction to Flexbox Lesson I
Introduction to Flexbox Lesson J
Introduction to Flexbox Lesson K
Learn Variables and Operators Lesson A
Learn Variables and Operators Lesson B
Learn Variables and Operators Lesson C
Learn Variables and Operators Lesson D
Learn Variables and Operators Lesson E
Learn Variables and Operators Lesson F
Learn Variables and Operators Lesson G
Learn Variables and Operators Lesson H
Learn Variables and Operators Lesson I
Learn Data Types and Conditionals Lesson A
Learn Data Types and Conditionals Lesson B
Learn Data Types and Conditionals Lesson C
Learn Data Types and Conditionals Lesson D
Learn Data Types and Conditionals Lesson E
Learn Data Types and Conditionals Lesson F
Learn Data Types and Conditionals Lesson G
Learn Data Types and Conditionals Lesson H
Learn Data Types and Conditionals Lesson I
Learn Data Types and Conditionals Lesson J
Learn Data Types and Conditionals Lesson K
Learn Data Types and Conditionals Lesson L
Learn Function Basics Lesson A
Learn Function Basics Lesson B
Learn Function Basics Lesson C
Learn Function Basics Lesson D
Learn Function Basics Lesson E
Learn Function Basics Lesson F
Basic Functions Exercise A
Basic Functions Exercise B
Basic Functions Exercise C
Basic Functions Exercise D
Learn Arrays and Loops Lesson A
Learn Arrays and Loops Lesson B
Learn Arrays and Loops Lesson C
Learn Arrays and Loops Lesson D
Learn Arrays and Loops Lesson E
Learn Arrays and Loops Lesson F
Learn Arrays and Loops Lesson G
Learn Arrays and Loops Lesson H
Learn to Solve Problems and Understand Errors Lesson A
Learn to Solve Problems and Understand Errors Lesson B
Learn to Solve Problems and Understand Errors Lesson C
Learn to Solve Problems and Understand Errors Lesson D
Learn to Solve Problems and Understand Errors Lesson E
Learn to Solve Problems and Understand Errors Lesson F
Learn to Solve Problems and Understand Errors Lesson G
Learn to Solve Problems and Understand Errors Lesson H
Build a Rock Paper Scissors Game
Find the Symmetric Difference
Inventory Update
No Repeats Please
Pairwise
Implement Bubble Sort
Implement Selection Sort
Implement Insertion Sort
Implement Quick Sort
Implement Merge Sort
Implement Binary Search
Typed Arrays
Learn how a Stack Works
Create a Stack Class
Create a Queue Class
Create a Priority Queue Class
Create a Circular Queue
Create a Set Class
Perform a Union on Two Sets
Perform an Intersection on Two Sets of Data
Perform a Difference on Two Sets of Data
Perform a Subset Check on Two Sets of Data
Create and Add to Sets in ES6
Remove items from a set in ES6
Use .has and .size on an ES6 Set
Use Spread and Notes for ES5 Set() Integration
Create a Map Data Structure
Create an ES6 JavaScript Map
Create a Hash Table
Work with Nodes in a Linked List
Create a Linked List Class
Remove Elements from a Linked List
Search within a Linked List
Remove Elements from a Linked List by Index
Add Elements at a Specific Index in a Linked List
Create a Doubly Linked List
Reverse a Doubly Linked List
Add a New Element to a Binary Search Tree
Find the Minimum and Maximum Value in a Binary Search Tree
Check if an Element is Present in a Binary Search Tree
Check if Tree is Binary Search Tree
Find the Minimum and Maximum Height of a Binary Search Tree
Use Depth First Search in a Binary Search Tree
Use Breadth First Search in a Binary Search Tree
Delete a Leaf Node in a Binary Search Tree
Delete a Node with One Child in a Binary Search Tree
Delete a Node with Two Children in a Binary Search Tree
Invert a Binary Tree
Create a Trie Search Tree
Insert an Element into a Max Heap
Remove an Element from a Max Heap
Implement Heap Sort with a Min Heap
Adjacency List
Adjacency Matrix
Incidence Matrix
Breadth-First Search
Depth-First Search
Show the Local Weather
Build a Wikipedia Viewer
Use the Twitch JSON API
Build an Image Search Abstraction Layer
Build a Tic Tac Toe Game
Build a Memory Light Game
Build a freeCodeCamp Forum Homepage
Build a Recipe Box
Build the Game of Life
Build a Roguelike Dungeon Crawler Game
P2P Video Chat Application
Show National Contiguity with a Force Directed Graph
Map Data Across the Globe
Manage a Book Trading Club
Build a Pinterest Clone
Build a Nightlife Coordination App
Chart the Stock Market
Build a Voting App
Build a Pong Game
Build a Light-Bright App
Problem 1: Multiples of 3 or 5
Problem 2: Even Fibonacci Numbers
Problem 3: Largest prime factor
Problem 4: Largest palindrome product
Problem 5: Smallest multiple
Problem 6: Sum square difference
Problem 7: 10001st prime
Problem 8: Largest product in a series
Problem 9: Special Pythagorean triplet
Problem 10: Summation of primes
Problem 11: Largest product in a grid
Problem 12: Highly divisible triangular number
Problem 13: Large sum
Problem 14: Longest Collatz sequence
Problem 15: Lattice paths
Problem 16: Power digit sum
Problem 17: Number letter counts
Problem 18: Maximum path sum I
Problem 19: Counting Sundays
Problem 20: Factorial digit sum
Problem 21: Amicable numbers
Problem 22: Names scores
Problem 23: Non-abundant sums
Problem 24: Lexicographic permutations
Problem 25: 1000-digit Fibonacci number
Problem 26: Reciprocal cycles
Problem 27: Quadratic primes
Problem 28: Number spiral diagonals
Problem 29: Distinct powers
Problem 30: Digit n powers
Problem 31: Coin sums
Problem 32: Pandigital products
Problem 33: Digit cancelling fractions
Problem 34: Digit factorials
Problem 35: Circular primes
Problem 36: Double-base palindromes
Problem 37: Truncatable primes
Problem 38: Pandigital multiples
Problem 39: Integer right triangles
Problem 40: Champernowne's constant
Problem 41: Pandigital prime
Problem 42: Coded triangle numbers
Problem 43: Sub-string divisibility
Problem 44: Pentagon numbers
Problem 45: Triangular, pentagonal, and hexagonal
Problem 46: Goldbach's other conjecture
Problem 47: Distinct primes factors
Problem 48: Self powers
Problem 49: Prime permutations
Problem 50: Consecutive prime sum
Problem 51: Prime digit replacements
Problem 52: Permuted multiples
Problem 53: Combinatoric selections
Problem 54: Poker hands
Problem 55: Lychrel numbers
Problem 56: Powerful digit sum
Problem 57: Square root convergents
Problem 58: Spiral primes
Problem 59: XOR decryption
Problem 60: Prime pair sets
Problem 61: Cyclical figurate numbers
Problem 62: Cubic permutations
Problem 63: Powerful digit counts
Problem 64: Odd period square roots
Problem 65: Convergents of e
Problem 66: Diophantine equation
Problem 67: Maximum path sum II
Problem 68: Magic 5-gon ring
Problem 69: Totient maximum
Problem 70: Totient permutation
Problem 71: Ordered fractions
Problem 72: Counting fractions
Problem 73: Counting fractions in a range
Problem 74: Digit factorial chains
Problem 75: Singular integer right triangles
Problem 76: Counting summations
Problem 77: Prime summations
Problem 78: Coin partitions
Problem 79: Passcode derivation
Problem 80: Square root digital expansion
Problem 81: Path sum: two ways
Problem 82: Path sum: three ways
Problem 83: Path sum: four ways
Problem 84: Monopoly odds
Problem 85: Counting rectangles
Problem 86: Cuboid route
Problem 87: Prime power triples
Problem 88: Product-sum numbers
Problem 89: Roman numerals
Problem 90: Cube digit pairs
Problem 91: Right triangles with integer coordinates
Problem 92: Square digit chains
Problem 93: Arithmetic expressions
Problem 94: Almost equilateral triangles
Problem 95: Amicable chains
Problem 96: Su Doku
Problem 97: Large non-Mersenne prime
Problem 98: Anagramic squares
Problem 99: Largest exponential
Problem 100: Arranged probability
Problem 101: Optimum polynomial
Problem 102: Triangle containment
Problem 103: Special subset sums: optimum
Problem 104: Pandigital Fibonacci ends
Problem 105: Special subset sums: testing
Problem 106: Special subset sums: meta-testing
Problem 107: Minimal network
Problem 108: Diophantine Reciprocals I
Problem 109: Darts
Problem 110: Diophantine Reciprocals II
Problem 111: Primes with runs
Problem 112: Bouncy numbers
Problem 113: Non-bouncy numbers
Problem 114: Counting block combinations I
Problem 115: Counting block combinations II
Problem 116: Red, green or blue tiles
Problem 117: Red, green, and blue tiles
Problem 118: Pandigital prime sets
Problem 119: Digit power sum
Problem 120: Square remainders
Problem 121: Disc game prize fund
Problem 122: Efficient exponentiation
Problem 123: Prime square remainders
Problem 124: Ordered radicals
Problem 125: Palindromic sums
Problem 126: Cuboid layers
Problem 127: abc-hits
Problem 128: Hexagonal tile differences
Problem 129: Repunit divisibility
Problem 130: Composites with prime repunit property
Problem 131: Prime cube partnership
Problem 132: Large repunit factors
Problem 133: Repunit nonfactors
Problem 134: Prime pair connection
Problem 135: Same differences
Problem 136: Singleton difference
Problem 137: Fibonacci golden nuggets
Problem 138: Special isosceles triangles
Problem 139: Pythagorean tiles
Problem 140: Modified Fibonacci golden nuggets
Problem 141: Investigating progressive numbers, n, which are also square
Problem 142: Perfect Square Collection
Problem 143: Investigating the Torricelli point of a triangle
Problem 144: Investigating multiple reflections of a laser beam
Problem 145: How many reversible numbers are there below one-billion?
Problem 146: Investigating a Prime Pattern
Problem 147: Rectangles in cross-hatched grids
Problem 148: Exploring Pascal's triangle
Problem 149: Searching for a maximum-sum subsequence
Problem 150: Searching a triangular array for a sub-triangle having minimum-sum
Problem 151: Paper sheets of standard sizes: an expected-value problem
Problem 152: Writing one half as a sum of inverse squares
Problem 153: Investigating Gaussian Integers
Problem 154: Exploring Pascal's pyramid
Problem 155: Counting Capacitor Circuits
Problem 156: Counting Digits
Problem 157: Solving the diophantine equation
Problem 158: Exploring strings for which only one character comes lexicographically after its neighbor to the left
Problem 159: Digital root sums of factorizations
Problem 160: Factorial trailing digits
Problem 161: Triominoes
Problem 162: Hexadecimal numbers
Problem 163: Cross-hatched triangles
Problem 164: Numbers for which no three consecutive digits have a sum greater than a given value
Problem 165: Intersections
Problem 166: Criss Cross
Problem 167: Investigating Ulam sequences
Problem 168: Number Rotations
Problem 169: Exploring the number of different ways a number can be expressed as a sum of powers of 2
Problem 170: Find the largest 0 to 9 pandigital that can be formed by concatenating products
Problem 171: Finding numbers for which the sum of the squares of the digits is a square
Problem 172: Investigating numbers with few repeated digits
Problem 173: Using up to one million tiles how many different "hollow" square laminae can be formed?
Problem 174: Counting the number of "hollow" square laminae that can form one, two, three, ... distinct arrangements
Problem 175: Fractions involving the number of different ways a number can be expressed as a sum of powers of 2
Problem 176: Right-angled triangles that share a cathetus
Problem 177: Integer angled Quadrilaterals
Problem 178: Step Numbers
Problem 179: Consecutive positive divisors
Problem 180: Rational zeros of a function of three variables
Problem 181: Investigating in how many ways objects of two different colors can be grouped
Problem 182: RSA encryption
Problem 183: Maximum product of parts
Problem 184: Triangles containing the origin
Problem 185: Number Mind
Problem 186: Connectedness of a network
Problem 187: Semiprimes
Problem 188: The hyperexponentiation of a number
Problem 189: Tri-coloring a triangular grid
Problem 190: Maximizing a weighted product
Problem 191: Prize Strings
Problem 192: Best Approximations
Problem 193: Squarefree Numbers
Problem 194: Colored Configurations
Problem 195: Inscribed circles of triangles with one angle of 60 degrees
Problem 196: Prime triplets
Problem 197: Investigating the behavior of a recursively defined sequence
Problem 198: Ambiguous Numbers
Problem 199: Iterative Circle Packing
Problem 200: Find the 200th prime-proof sqube containing the contiguous sub-string "200"
Problem 201: Subsets with a unique sum
Problem 202: Laserbeam
Problem 203: Squarefree Binomial Coefficients
Problem 204: Generalised Hamming Numbers
Problem 205: Dice Game
Problem 206: Concealed Square
Problem 207: Integer partition equations
Problem 208: Robot Walks
Problem 209: Circular Logic
Problem 210: Obtuse Angled Triangles
Problem 211: Divisor Square Sum
Problem 212: Combined Volume of Cuboids
Problem 213: Flea Circus
Problem 214: Totient Chains
Problem 215: Crack-free Walls
Problem 216: Investigating the primality of numbers of the form 2n2-1
Problem 217: Balanced Numbers
Problem 218: Perfect right-angled triangles
Problem 219: Skew-cost coding
Problem 220: Heighway Dragon
Problem 221: Alexandrian Integers
Problem 222: Sphere Packing
Problem 223: Almost right-angled triangles I
Problem 224: Almost right-angled triangles II
Problem 225: Tribonacci non-divisors
Problem 226: A Scoop of Blancmange
Problem 227: The Chase
Problem 228: Minkowski Sums
Problem 229: Four Representations using Squares
Problem 230: Fibonacci Words
Problem 231: The prime factorisation of binomial coefficients
Problem 232: The Race
Problem 233: Lattice points on a circle
Problem 234: Semidivisible numbers
Problem 235: An Arithmetic Geometric sequence
Problem 236: Luxury Hampers
Problem 237: Tours on a 4 x n playing board
Problem 238: Infinite string tour
Problem 239: Twenty-two Foolish Primes
Problem 240: Top Dice
Problem 241: Perfection Quotients
Problem 242: Odd Triplets
Problem 243: Resilience
Problem 244: Sliders
Problem 245: Coresilience
Problem 246: Tangents to an ellipse
Problem 247: Squares under a hyperbola
Problem 248: Numbers for which Euler’s totient function equals 13!
Problem 249: Prime Subset Sums
Problem 250: 250250
Problem 251: Cardano Triplets
Problem 252: Convex Holes
Problem 253: Tidying up
Problem 254: Sums of Digit Factorials
Problem 255: Rounded Square Roots
Problem 256: Tatami-Free Rooms
Problem 257: Angular Bisectors
Problem 258: A lagged Fibonacci sequence
Problem 259: Reachable Numbers
Problem 260: Stone Game
Problem 261: Pivotal Square Sums
Problem 262: Mountain Range
Problem 263: An engineers' dream come true
Problem 264: Triangle Centers
Problem 265: Binary Circles
Problem 266: Pseudo Square Root
Problem 267: Billionaire
Problem 268: Counting numbers with at least four distinct prime factors less than 100
Problem 269: Polynomials with at least one integer root
Problem 270: Cutting Squares
Problem 271: Modular Cubes, part 1
Problem 272: Modular Cubes, part 2
Problem 273: Sum of Squares
Problem 274: Divisibility Multipliers
Problem 275: Balanced Sculptures
Problem 276: Primitive Triangles
Problem 277: A Modified Collatz sequence
Problem 278: Linear Combinations of Semiprimes
Problem 279: Triangles with integral sides and an integral angle
Problem 280: Ant and seeds
Problem 281: Pizza Toppings
Problem 282: The Ackermann function
Problem 283: Integer sided triangles for which the area / perimeter ratio is integral
Problem 284: Steady Squares
Problem 285: Pythagorean odds
Problem 286: Scoring probabilities
Problem 287: Quadtree encoding (a simple compression algorithm)
Problem 288: An enormous factorial
Problem 289: Eulerian Cycles
Problem 290: Digital Signature
Problem 291: Panaitopol Primes
Problem 292: Pythagorean Polygons
Problem 293: Pseudo-Fortunate Numbers
Problem 294: Sum of digits - experience #23
Problem 295: Lenticular holes
Problem 296: Angular Bisector and Tangent
Problem 297: Zeckendorf Representation
Problem 298: Selective Amnesia
Problem 299: Three similar triangles
Problem 300: Protein folding
Problem 301: Nim
Problem 302: Strong Achilles Numbers
Problem 303: Multiples with small digits
Problem 304: Primonacci
Problem 305: Reflexive Position
Problem 306: Paper-strip Game
Problem 307: Chip Defects
Problem 308: An amazing Prime-generating Automaton
Problem 309: Integer Ladders
Problem 310: Nim Square
Problem 311: Biclinic Integral Quadrilaterals
Problem 312: Cyclic paths on Sierpiński graphs
Problem 313: Sliding game
Problem 314: The Mouse on the Moon
Problem 315: Digital root clocks
Problem 316: Numbers in decimal expansions
Problem 317: Firecracker
Problem 318: 2011 nines
Problem 319: Bounded Sequences
Problem 320: Factorials divisible by a huge integer
Problem 321: Swapping Counters
Problem 322: Binomial coefficients divisible by 10
Problem 323: Bitwise-OR operations on random integers
Problem 324: Building a tower
Problem 325: Stone Game II
Problem 326: Modulo Summations
Problem 327: Rooms of Doom
Problem 328: Lowest-cost Search
Problem 329: Prime Frog
Problem 330: Euler's Number
Problem 331: Cross flips
Problem 332: Spherical triangles
Problem 333: Special partitions
Problem 334: Spilling the beans
Problem 335: Gathering the beans
Problem 336: Maximix Arrangements
Problem 337: Totient Stairstep Sequences
Problem 338: Cutting Rectangular Grid Paper
Problem 339: Peredur fab Efrawg
Problem 340: Crazy Function
Problem 341: Golomb's self-describing sequence
Problem 342: The totient of a square is a cube
Problem 343: Fractional Sequences
Problem 344: Silver dollar game
Problem 345: Matrix Sum
Problem 346: Strong Repunits
Problem 347: Largest integer divisible by two primes
Problem 348: Sum of a square and a cube
Problem 349: Langton's ant
Problem 350: Constraining the least greatest and the greatest least
Problem 351: Hexagonal orchards
Problem 352: Blood tests
Problem 353: Risky moon
Problem 354: Distances in a bee's honeycomb
Problem 355: Maximal coprime subset
Problem 356: Largest roots of cubic polynomials
Problem 357: Prime generating integers
Problem 358: Cyclic numbers
Problem 359: Hilbert's New Hotel
Problem 360: Scary Sphere
Problem 361: Subsequence of Thue-Morse sequence
Problem 362: Squarefree factors
Problem 363: Bézier Curves
Problem 364: Comfortable distance
Problem 365: A huge binomial coefficient
Problem 366: Stone Game III
Problem 367: Bozo sort
Problem 368: A Kempner-like series
Problem 369: Badugi
Problem 370: Geometric triangles
Problem 371: License plates
Problem 372: Pencils of rays
Problem 373: Circumscribed Circles
Problem 374: Maximum Integer Partition Product
Problem 375: Minimum of subsequences
Problem 376: Nontransitive sets of dice
Problem 377: Sum of digits, experience 13
Problem 378: Triangle Triples
Problem 379: Least common multiple count
Problem 380: Amazing Mazes!
Problem 381: (prime-k) factorial
Problem 382: Generating polygons
Problem 383: Divisibility comparison between factorials
Problem 384: Rudin-Shapiro sequence
Problem 385: Ellipses inside triangles
Problem 386: Maximum length of an antichain
Problem 387: Harshad Numbers
Problem 388: Distinct Lines
Problem 389: Platonic Dice
Problem 390: Triangles with non rational sides and integral area
Problem 391: Hopping Game
Problem 392: Enmeshed unit circle
Problem 393: Migrating ants
Problem 394: Eating pie
Problem 395: Pythagorean tree
Problem 396: Weak Goodstein sequence
Problem 397: Triangle on parabola
Problem 398: Cutting rope
Problem 399: Squarefree Fibonacci Numbers
Problem 400: Fibonacci tree game
Problem 401: Sum of squares of divisors
Problem 402: Integer-valued polynomials
Problem 403: Lattice points enclosed by parabola and line
Problem 404: Crisscross Ellipses
Problem 405: A rectangular tiling
Problem 406: Guessing Game
Problem 407: Idempotents
Problem 408: Admissible paths through a grid
Problem 409: Nim Extreme
Problem 410: Circle and tangent line
Problem 411: Uphill paths
Problem 412: Gnomon numbering
Problem 413: One-child Numbers
Problem 414: Kaprekar constant
Problem 415: Titanic sets
Problem 416: A frog's trip
Problem 417: Reciprocal cycles II
Problem 418: Factorisation triples
Problem 419: Look and say sequence
Problem 420: 2x2 positive integer matrix
Problem 421: Prime factors of n^15+1
Problem 422: Sequence of points on a hyperbola
Problem 423: Consecutive die throws
Problem 424: Kakuro
Problem 425: Prime connection
Problem 426: Box-ball system
Problem 427: n-sequences
Problem 428: Necklace of Circles
Problem 429: Sum of squares of unitary divisors
Problem 430: Range flips
Problem 431: Square Space Silo
Problem 432: Totient sum
Problem 433: Steps in Euclid's algorithm
Problem 434: Rigid graphs
Problem 435: Polynomials of Fibonacci numbers
Problem 436: Unfair wager
Problem 437: Fibonacci primitive roots
Problem 438: Integer part of polynomial equation's solutions
Problem 439: Sum of sum of divisors
Problem 440: GCD and Tiling
Problem 441: The inverse summation of coprime couples
Problem 442: Eleven-free integers
Problem 443: GCD sequence
Problem 444: The Roundtable Lottery
Problem 445: Retractions A
Problem 446: Retractions B
Problem 447: Retractions C
Problem 448: Average least common multiple
Problem 449: Chocolate covered candy
Problem 450: Hypocycloid and Lattice points
Problem 451: Modular inverses
Problem 452: Long Products
Problem 453: Lattice Quadrilaterals
Problem 454: Diophantine reciprocals III
Problem 455: Powers With Trailing Digits
Problem 456: Triangles containing the origin II
Problem 457: A polynomial modulo the square of a prime
Problem 458: Permutations of Project
Problem 459: Flipping game
Problem 460: An ant on the move
Problem 461: Almost Pi
Problem 462: Permutation of 3-smooth numbers
Problem 463: A weird recurrence relation
Problem 464: Möbius function and intervals
Problem 465: Polar polygons
Problem 466: Distinct terms in a multiplication table
Problem 467: Superinteger
Problem 468: Smooth divisors of binomial coefficients
Problem 469: Empty chairs
Problem 470: Super Ramvok
Problem 471: Triangle inscribed in ellipse
Problem 472: Comfortable Distance II
Problem 473: Phigital number base
Problem 474: Last digits of divisors
Problem 475: Music festival
Problem 476: Circle Packing II
Problem 477: Number Sequence Game
Problem 478: Mixtures
Problem 479: Roots on the Rise
Problem 480: The Last Question
100 doors
24 game
9 billion names of God the integer
ABC Problem
Abundant, deficient and perfect number classifications
Accumulator factory
Ackermann function
Align columns
Amicable pairs
Averages/Mode
Averages/Pythagorean means
Averages/Root mean square
Babbage problem
Balanced brackets
Circles of given radius through two points
Closest-pair problem
Combinations
Comma quibbling
Compare a list of strings
Convert seconds to compound duration
Count occurrences of a substring
Count the coins
Cramer's rule
Cumulative standard deviation
CUSIP
Cut a rectangle
Date format
Date manipulation
Day of the week
Deal cards for FreeCell
Deepcopy
Define a primitive data type
Department Numbers
Discordian date
Dot product
Element-wise operations
Emirp primes
Entropy
Equilibrium index
Ethiopian multiplication
Euler method
Evaluate binomial coefficients
Execute a Markov algorithm
Execute Brain****
Extensible prime generator
Factorial
Factors of a Mersenne number
Factors of an integer
Farey sequence
Fibonacci n-step number sequences
Fibonacci sequence
Fibonacci word
FizzBuzz
Fractran
Gamma function
Gaussian elimination
General FizzBuzz
Generate lower case ASCII alphabet
Generator/Exponential
Gray code
Greatest common divisor
Greatest subsequential sum
Hailstone sequence
Happy numbers
Harshad or Niven series
Hash from two arrays
Hash join
Heronian triangles
Hofstadter Figure-Figure sequences
Hofstadter Q sequence
I before E except after C
IBAN
Identity matrix
Iterated digits squaring
Jaro distance
JortSort
Josephus problem
K-d tree
Kaprekar numbers
Knapsack problem/0-1
Knapsack problem/Bounded
Knapsack problem/Continuous
Knapsack problem/Unbounded
Knight's tour
Largest int from concatenated ints
Last letter-first letter
Last Friday of each month
Leap year
Least common multiple
Left factorials
Letter frequency
Levenshtein distance
Linear congruential generator
Long multiplication
Longest common subsequence
Longest increasing subsequence
Longest string challenge
Look-and-say sequence
Loop over multiple arrays simultaneously
LU decomposition
Lucas-Lehmer test
Ludic numbers
Luhn test of credit card numbers
Lychrel numbers
LZW compression
S-Expressions
Sailors, coconuts and a monkey problem
Search a list of records
SEDOLs
Self Describing Numbers
Self-referential sequence
Semiprime
Set consolidation
Set of real numbers
SHA-1
SHA-256
Sort an array of composite structures
Sort disjoint sublist
Sort stability
Sort using a custom comparator
Sorting algorithms/Bead sort
Sorting algorithms/Bogosort
Sorting algorithms/Cocktail sort
Sorting algorithms/Comb sort
Sorting algorithms/Gnome sort
Sorting algorithms/Pancake sort
Sorting algorithms/Permutation sort
Sorting algorithms/Shell sort
Sorting algorithms/Stooge sort
Sorting algorithms/Strand sort
Soundex
Spiral matrix
Split a character string based on change of character
State name puzzle
Stern-Brocot sequence
Straddling checkerboard
Stream Merge
Strip control codes and extended characters from a string
Subleq
Sudoku
Sum digits of an integer
Sum multiples of 3 and 5
Sum of a series
Sum of squares
Sum to 100
Sutherland-Hodgman polygon clipping
Symmetric difference
Taxicab numbers
Tokenize a string with escaping
Topological sort
Top rank per group
Towers of Hanoi
Vector cross product
Vector dot product
Word frequency
Word wrap
Y combinator
Zeckendorf number representation
Zhang-Suen thinning algorithm
Zig-zag matrix
Step 116
Step 117
Step 118
Build a Personal Portfolio Webpage
Step 119
Step 120
Step 121
Step 122
Step 123
Step 124
Step 125
Step 126
Step 127
Step 128
Step 129
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Step 170
Step 171
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Step 173
Build a Roman Numeral Converter
Build a Telephone Number Validator
Build a Cash Register
Build an RPG Creature Search App
Use Responsive Design with Bootstrap Fluid Containers
Make Images Mobile Responsive
Center Text with Bootstrap
Create a Bootstrap Button
Create a Block Element Bootstrap Button
Taste the Bootstrap Button Color Rainbow
Call out Optional Actions with btn-info
Warn Your Users of a Dangerous Action with btn-danger
Use the Bootstrap Grid to Put Elements Side By Side
Ditch Custom CSS for Bootstrap
Use a span to Target Inline Elements
Create a Custom Heading
Add Font Awesome Icons to our Buttons
Add Font Awesome Icons to all of our Buttons
Responsively Style Radio Buttons
Responsively Style Checkboxes
Style Text Inputs as Form Controls
Line up Form Elements Responsively with Bootstrap
Create a Bootstrap Headline
House our page within a Bootstrap container-fluid div
Create a Bootstrap Row
Split Your Bootstrap Row
Create Bootstrap Wells
Add Elements within Your Bootstrap Wells
Apply the Default Bootstrap Button Style
Create a Class to Target with jQuery Selectors
Add id Attributes to Bootstrap Elements
Label Bootstrap Wells
Give Each Element a Unique id
Label Bootstrap Buttons
Use Comments to Clarify Code
Learn How Script Tags and Document Ready Work
Target HTML Elements with Selectors Using jQuery
Target Elements by Class Using jQuery
Target Elements by id Using jQuery
Delete Your jQuery Functions
Target the Same Element with Multiple jQuery Selectors
Remove Classes from an Element with jQuery
Change the CSS of an Element Using jQuery
Disable an Element Using jQuery
Change Text Inside an Element Using jQuery
Remove an Element Using jQuery
Use appendTo to Move Elements with jQuery
Clone an Element Using jQuery
Target the Parent of an Element Using jQuery
Target the Children of an Element Using jQuery
Target a Specific Child of an Element Using jQuery
Target Even Elements Using jQuery
Use jQuery to Modify the Entire Page
Store Data with Sass Variables
Nest CSS with Sass
Create Reusable CSS with Mixins
Use @if and @else to Add Logic To Your Styles
Use @for to Create a Sass Loop
Use @each to Map Over Items in a List
Apply a Style Until a Condition is Met with @while
Split Your Styles into Smaller Chunks with Partials
Extend One Set of CSS Styles to Another Element
Create a Simple JSX Element
Create a Complex JSX Element
Add Comments in JSX
Render HTML Elements to the DOM
Define an HTML Class in JSX
Learn About Self-Closing JSX Tags
Create a Stateless Functional Component
Create a React Component
Create a Component with Composition
Use React to Render Nested Components
Compose React Components
Render a Class Component to the DOM
Write a React Component from Scratch
Pass Props to a Stateless Functional Component
Pass an Array as Props
Use Default Props
Override Default Props
Use PropTypes to Define the Props You Expect
Access Props Using this.props
Review Using Props with Stateless Functional Components
Create a Stateful Component
Render State in the User Interface
Render State in the User Interface Another Way
Set State with this.setState
Bind 'this' to a Class Method
Use State to Toggle an Element
Write a Simple Counter
Create a Controlled Input
Create a Controlled Form
Pass State as Props to Child Components
Pass a Callback as Props
Use the Lifecycle Method componentWillMount
Use the Lifecycle Method componentDidMount
Add Event Listeners
Optimize Re-Renders with shouldComponentUpdate
Introducing Inline Styles
Add Inline Styles in React
Use Advanced JavaScript in React Render Method
Render with an If-Else Condition
Use && for a More Concise Conditional
Use a Ternary Expression for Conditional Rendering
Render Conditionally from Props
Change Inline CSS Conditionally Based on Component State
Use Array.map() to Dynamically Render Elements
Give Sibling Elements a Unique Key Attribute
Use Array.filter() to Dynamically Filter an Array
Render React on the Server with renderToString
Create a Redux Store
Get State from the Redux Store
Define a Redux Action
Define an Action Creator
Dispatch an Action Event
Handle an Action in the Store
Use a Switch Statement to Handle Multiple Actions
Use const for Action Types
Register a Store Listener
Combine Multiple Reducers
Send Action Data to the Store
Use Middleware to Handle Asynchronous Actions
Write a Counter with Redux
Never Mutate State
Use the Spread Operator on Arrays
Remove an Item from an Array
Copy an Object with Object.assign
Getting Started with React Redux
Manage State Locally First
Extract State Logic to Redux
Use Provider to Connect Redux to React
Map State to Props
Map Dispatch to Props
Connect Redux to React
Connect Redux to the Messages App
Extract Local State into Redux
Moving Forward From Here
Build a Random Quote Machine
Build a Markdown Previewer
Build a JavaScript Calculator
Build a 25 + 5 Clock
Add Document Elements with D3
Select a Group of Elements with D3
Work with Data in D3
Work with Dynamic Data in D3
Add Inline Styling to Elements
Change Styles Based on Data
Add Classes with D3
Update the Height of an Element Dynamically
Change the Presentation of a Bar Chart
Learn About SVG in D3
Display Shapes with SVG
Create a Bar for Each Data Point in the Set
Dynamically Set the Coordinates for Each Bar
Dynamically Change the Height of Each Bar
Invert SVG Elements
Change the Color of an SVG Element
Add Labels to D3 Elements
Style D3 Labels
Add a Hover Effect to a D3 Element
Add a Tooltip to a D3 Element
Create a Scatterplot with SVG Circles
Add Attributes to the Circle Elements
Add Labels to Scatter Plot Circles
Create a Linear Scale with D3
Set a Domain and a Range on a Scale
Use the d3.max and d3.min Functions to Find Minimum and Maximum Values in a Dataset
Use Dynamic Scales
Use a Pre-Defined Scale to Place Elements
Add Axes to a Visualization
Handle Click Events with JavaScript using the onclick property
Change Text with click Events
Get JSON with the JavaScript XMLHttpRequest Method
Get JSON with the JavaScript fetch method
Access the JSON Data from an API
Convert JSON Data to HTML
Render Images from Data Sources
Pre-filter JSON to Get the Data You Need
Get Geolocation Data to Find A User's GPS Coordinates
Post Data with the JavaScript XMLHttpRequest Method
Visualize Data with a Bar Chart
Visualize Data with a Scatterplot Graph
Visualize Data with a Heat Map
Visualize Data with a Choropleth Map
Visualize Data with a Treemap Diagram
How to Use package.json, the Core of Any Node.js Project or npm Package
Add a Description to Your package.json
Add Keywords to Your package.json
Add a License to Your package.json
Add a Version to Your package.json
Expand Your Project with External Packages from npm
Manage npm Dependencies By Understanding Semantic Versioning
Use the Tilde-Character to Always Use the Latest Patch Version of a Dependency
Use the Caret-Character to Use the Latest Minor Version of a Dependency
Remove a Package from Your Dependencies
Meet the Node console
Start a Working Express Server
Serve an HTML File
Serve Static Assets
Serve JSON on a Specific Route
Use the .env File
Implement a Root-Level Request Logger Middleware
Chain Middleware to Create a Time Server
Get Route Parameter Input from the Client
Get Query Parameter Input from the Client
Use body-parser to Parse POST Requests
Get Data from POST Requests
Install and Set Up Mongoose
Create a Model
Create and Save a Record of a Model
Create Many Records with model.create()
Use model.find() to Search Your Database
Use model.findOne() to Return a Single Matching Document from Your Database
Use model.findById() to Search Your Database By _id
Perform Classic Updates by Running Find, Edit, then Save
Perform New Updates on a Document Using model.findOneAndUpdate()
Delete One Document Using model.findByIdAndRemove
Delete Many Documents with model.remove()
Chain Search Query Helpers to Narrow Search Results
Timestamp Microservice
Request Header Parser Microservice
URL Shortener Microservice
Exercise Tracker
File Metadata Microservice
Learn How JavaScript Assertions Work
Test if a Variable or Function is Defined
Use Assert.isOK and Assert.isNotOK
Test for Truthiness
Use the Double Equals to Assert Equality
Use the Triple Equals to Assert Strict Equality
Assert Deep Equality with .deepEqual and .notDeepEqual
Compare the Properties of Two Elements
Test if One Value is Below or At Least as Large as Another
Test if a Value Falls within a Specific Range
Test if a Value is an Array
Test if an Array Contains an Item
Test if a Value is a String
Test if a String Contains a Substring
Use Regular Expressions to Test a String
Test if an Object has a Property
Test if a Value is of a Specific Data Structure Type
Test if an Object is an Instance of a Constructor
Run Functional Tests on API Endpoints using Chai-HTTP
Run Functional Tests on API Endpoints using Chai-HTTP II
Run Functional Tests on an API Response using Chai-HTTP III - PUT method
Run Functional Tests on an API Response using Chai-HTTP IV - PUT method
Simulate Actions Using a Headless Browser
Run Functional Tests Using a Headless Browser
Run Functional Tests Using a Headless Browser II
Set up a Template Engine
Use a Template Engine's Powers
Set up Passport
Serialization of a User Object
Implement the Serialization of a Passport User
Authentication Strategies
How to Use Passport Strategies
Create New Middleware
How to Put a Profile Together
Logging a User Out
Registration of New Users
Hashing Your Passwords
Clean Up Your Project with Modules
Implementation of Social Authentication
Implementation of Social Authentication II
Implementation of Social Authentication III
Set up the Environment
Communicate by Emitting
Handle a Disconnect
Authentication with Socket.IO
Announce New Users
Send and Display Chat Messages
Metric-Imperial Converter
Issue Tracker
Personal Library
Sudoku Solver
American British Translator
Build an Arithmetic Formatter Project
Build a Time Calculator Project
Build a Budget App Project
Build a Polygon Area Calculator Project
Build a Probability Calculator Project
Introduction to Data Analysis
Data Analysis Example A
Data Analysis Example B
How to use Jupyter Notebooks Intro
Jupyter Notebooks Cells
Jupyter Notebooks Importing and Exporting Data
Numpy Introduction A
Numpy Introduction B
Numpy Arrays
Numpy Operations
Numpy Boolean Arrays
Numpy Algebra and Size
Pandas Introduction
Pandas Indexing and Conditional Selection
Pandas DataFrames
Pandas Conditional Selection and Modifying DataFrames
Pandas Creating Columns
Data Cleaning Introduction
Data Cleaning with DataFrames
Data Cleaning Duplicates
Data Cleaning and Visualizations
Reading Data Introduction
Reading Data CSV and TXT
Reading Data from Databases
Parsing HTML and Saving Data
Python Introduction
Python Functions and Collections
Python Iteration and Modules
What is NumPy
Basics of Numpy
Accessing and Changing Elements, Rows, Columns
Initializing Different Arrays
Initialize Array Problem
Copying Arrays Warning
Mathematics
Reorganizing Arrays
Loading Data and Advanced Indexing
Mean-Variance-Standard Deviation Calculator
Demographic Data Analyzer
Medical Data Visualizer
Page View Time Series Visualizer
Sea Level Predictor
Install and Require Helmet
Hide Potentially Dangerous Information Using helmet.hidePoweredBy()
Mitigate the Risk of Clickjacking with helmet.frameguard()
Mitigate the Risk of Cross Site Scripting (XSS) Attacks with helmet.xssFilter()
Avoid Inferring the Response MIME Type with helmet.noSniff()
Prevent IE from Opening Untrusted HTML with helmet.ieNoOpen()
Ask Browsers to Access Your Site via HTTPS Only with helmet.hsts()
Disable DNS Prefetching with helmet.dnsPrefetchControl()
Disable Client-Side Caching with helmet.noCache()
Set a Content Security Policy with helmet.contentSecurityPolicy()
Configure Helmet Using the ‘parent’ helmet() Middleware
Understand BCrypt Hashes
Hash and Compare Passwords Asynchronously
Hash and Compare Passwords Synchronously
Introduction and Setup
Understanding Sockets and Creating a TCP Server
Creating a TCP Client
Developing an Nmap Scanner part 1
Developing an Nmap Scanner part 2
Developing a Banner Grabber
Developing a Port Scanner
Stock Price Checker
Anonymous Message Board
Port Scanner
SHA-1 Password Cracker
Secure Real Time Multiplayer Game
Introduction: Machine Learning Fundamentals
Introduction to TensorFlow
Core Learning Algorithms
Core Learning Algorithms: Working with Data
Core Learning Algorithms: Training and Testing Data
Core Learning Algorithms: The Training Process
Core Learning Algorithms: Classification
Core Learning Algorithms: Building the Model
Core Learning Algorithms: Clustering
Core Learning Algorithms: Hidden Markov Models
Core Learning Algorithms: Using Probabilities to make Predictions
Neural Networks with TensorFlow
Neural Networks: Activation Functions
Neural Networks: Optimizers
Neural Networks: Creating a Model
Convolutional Neural Networks
Convolutional Neural Networks: The Convolutional Layer
Creating a Convolutional Neural Network
Convolutional Neural Networks: Evaluating the Model
Convolutional Neural Networks: Picking a Pretrained Model
Natural Language Processing With RNNs
Natural Language Processing With RNNs: Part 2
Natural Language Processing With RNNs: Recurring Neural Networks
Natural Language Processing With RNNs: Sentiment Analysis
Natural Language Processing With RNNs: Making Predictions
Natural Language Processing With RNNs: Create a Play Generator
Natural Language Processing With RNNs: Building the Model
Natural Language Processing With RNNs: Training the Model
Reinforcement Learning With Q-Learning
Reinforcement Learning With Q-Learning: Part 2
Reinforcement Learning With Q-Learning: Example
Conclusion
How Deep Neural Networks Work
Recurrent Neural Networks RNN and Long Short Term Memory LSTM
Deep Learning Demystified
How Convolutional Neural Networks work
Rock Paper Scissors
Cat and Dog Image Classifier
Book Recommendation Engine using KNN
Linear Regression Health Costs Calculator
Neural Network SMS Text Classifier
Introduction to College Algebra with Python
Solving Proportions
Ratios and Proportions: Extra
Solving for X
How to Solve for X: Extra
Converting Fractions and Decimals
Fractions and Decimals: Extra
Functions
Graphing
Functions and Graphing: Extra
Slope
Linear Equations
Linear Functions: Extra
Factoring
Build a Multi-Function Calculator
Graphing Systems
Graphing Systems of Equations: Extra
Solving Systems
Solving Systems of Equations: Extra
Word Problems
Applications of Linear Systems: Extra
Quadratics
Build a Graphing Calculator
Parent Graphs
Parent Graphs and Polynomials: Extra
Build Three Math Games
Demand and Revenue
Business Applications of College Algebra: Extra
Simple and Compound Interest
Simple and Compound Interest: Extra
Exponents and Logarithms
Build a Financial Calculator
Spreadsheets and Additional Resources
More Resources in Colab
Build a Data Graph Explorer
Say Hello to HTML Elements
Headline with the h2 Element
Inform with the Paragraph Element
Fill in the Blank with Placeholder Text
Uncomment HTML
Comment out HTML
Delete HTML Elements
Introduction to HTML5 Elements
Add Images to Your Website
Link to External Pages with Anchor Elements
Link to Internal Sections of a Page with Anchor Elements
Nest an Anchor Element within a Paragraph
Make Dead Links Using the Hash Symbol
Turn an Image into a Link
Create a Bulleted Unordered List
Create an Ordered List
Create a Text Field
Add Placeholder Text to a Text Field
Create a Form Element
Add a Submit Button to a Form
Use HTML5 to Require a Field
Create a Set of Radio Buttons
Create a Set of Checkboxes
Use the value attribute with Radio Buttons and Checkboxes
Check Radio Buttons and Checkboxes by Default
Nest Many Elements within a Single div Element
Declare the Doctype of an HTML Document
Define the Head and Body of an HTML Document
Change the Color of Text
Use CSS Selectors to Style Elements
Use a CSS Class to Style an Element
Style Multiple Elements with a CSS Class
Change the Font Size of an Element
Set the Font Family of an Element
Import a Google Font
Specify How Fonts Should Degrade
Size Your Images
Add Borders Around Your Elements
Add Rounded Corners with border-radius
Make Circular Images with a border-radius
Give a Background Color to a div Element
Set the id of an Element
Use an id Attribute to Style an Element
Adjust the Padding of an Element
Adjust the Margin of an Element
Add a Negative Margin to an Element
Add Different Padding to Each Side of an Element
Add Different Margins to Each Side of an Element
Use Clockwise Notation to Specify the Padding of an Element
Use Clockwise Notation to Specify the Margin of an Element
Use Attribute Selectors to Style Elements
Understand Absolute versus Relative Units
Style the HTML Body Element
Inherit Styles from the Body Element
Prioritize One Style Over Another
Override Styles in Subsequent CSS
Override Class Declarations by Styling ID Attributes
Override Class Declarations with Inline Styles
Override All Other Styles by using Important
Use Hex Code for Specific Colors
Use Hex Code to Mix Colors
Use Abbreviated Hex Code
Use RGB values to Color Elements
Use RGB to Mix Colors
Use CSS Variables to change several elements at once
Create a custom CSS Variable
Use a custom CSS Variable
Attach a Fallback value to a CSS Variable
Improve Compatibility with Browser Fallbacks
Inherit CSS Variables
Change a variable for a specific area
Use a media query to change a variable
Create Visual Balance Using the text-align Property
Adjust the Width of an Element Using the width Property
Adjust the Height of an Element Using the height Property
Use the strong Tag to Make Text Bold
Use the u Tag to Underline Text
Use the em Tag to Italicize Text
Use the s Tag to Strikethrough Text
Create a Horizontal Line Using the hr Element
Adjust the background-color Property of Text
Adjust the Size of a Heading Element Versus a Paragraph Element
Add a box-shadow to a Card-like Element
Decrease the Opacity of an Element
Use the text-transform Property to Make Text Uppercase
Set the font-size for Multiple Heading Elements
Set the font-weight for Multiple Heading Elements
Set the font-size of Paragraph Text
Set the line-height of Paragraphs
Adjust the Hover State of an Anchor Tag
Change an Element's Relative Position
Move a Relatively Positioned Element with CSS Offsets
Lock an Element to its Parent with Absolute Positioning
Lock an Element to the Browser Window with Fixed Positioning
Push Elements Left or Right with the float Property
Change the Position of Overlapping Elements with the z-index Property
Center an Element Horizontally Using the margin Property
Learn about Complementary Colors
Learn about Tertiary Colors
Adjust the Color of Various Elements to Complementary Colors
Adjust the Hue of a Color
Adjust the Tone of a Color
Create a Gradual CSS Linear Gradient
Use a CSS Linear Gradient to Create a Striped Element
Create Texture by Adding a Subtle Pattern as a Background Image
Use the CSS Transform scale Property to Change the Size of an Element
Use the CSS Transform scale Property to Scale an Element on Hover
Use the CSS Transform Property skewX to Skew an Element Along the X-Axis
Use the CSS Transform Property skewY to Skew an Element Along the Y-Axis
Create a Graphic Using CSS
Create a More Complex Shape Using CSS and HTML
Learn How the CSS @keyframes and animation Properties Work
Use CSS Animation to Change the Hover State of a Button
Modify Fill Mode of an Animation
Create Movement Using CSS Animation
Create Visual Direction by Fading an Element from Left to Right
Animate Elements Continually Using an Infinite Animation Count
Make a CSS Heartbeat using an Infinite Animation Count
Animate Elements at Variable Rates
Animate Multiple Elements at Variable Rates
Change Animation Timing with Keywords
Learn How Bezier Curves Work
Use a Bezier Curve to Move a Graphic
Make Motion More Natural Using a Bezier Curve
Add a Text Alternative to Images for Visually Impaired Accessibility
Know When Alt Text Should be Left Blank
Use Headings to Show Hierarchical Relationships of Content
Jump Straight to the Content Using the main Element
Wrap Content in the article Element
Make Screen Reader Navigation Easier with the header Landmark
Make Screen Reader Navigation Easier with the nav Landmark
Make Screen Reader Navigation Easier with the footer Landmark
Improve Accessibility of Audio Content with the audio Element
Improve Chart Accessibility with the figure Element
Improve Form Field Accessibility with the label Element
Wrap Radio Buttons in a fieldset Element for Better Accessibility
Add an Accessible Date Picker
Standardize Times with the HTML5 datetime Attribute
Make Elements Only Visible to a Screen Reader by Using Custom CSS
Improve Readability with High Contrast Text
Avoid Colorblindness Issues by Using Sufficient Contrast
Avoid Colorblindness Issues by Carefully Choosing Colors that Convey Information
Give Links Meaning by Using Descriptive Link Text
Make Links Navigable with HTML Access Keys
Use tabindex to Add Keyboard Focus to an Element
Use tabindex to Specify the Order of Keyboard Focus for Several Elements
Create a Media Query
Make an Image Responsive
Use a Retina Image for Higher Resolution Displays
Make Typography Responsive
Use display: flex to Position Two Boxes
Add Flex Superpowers to the Tweet Embed
Use the flex-direction Property to Make a Row
Apply the flex-direction Property to Create Rows in the Tweet Embed
Use the flex-direction Property to Make a Column
Apply the flex-direction Property to Create a Column in the Tweet Embed
Align Elements Using the justify-content Property
Use the justify-content Property in the Tweet Embed
Align Elements Using the align-items Property
Use the align-items Property in the Tweet Embed
Use the flex-wrap Property to Wrap a Row or Column
Use the flex-shrink Property to Shrink Items
Use the flex-grow Property to Expand Items
Use the flex-basis Property to Set the Initial Size of an Item
Use the flex Shorthand Property
Use the order Property to Rearrange Items
Use the align-self Property
Create Your First CSS Grid
Add Columns with grid-template-columns
Add Rows with grid-template-rows
Use CSS Grid units to Change the Size of Columns and Rows
Create a Column Gap Using grid-column-gap
Create a Row Gap using grid-row-gap
Add Gaps Faster with grid-gap
Use grid-column to Control Spacing
Use grid-row to Control Spacing
Align an Item Horizontally using justify-self
Align an Item Vertically using align-self
Align All Items Horizontally using justify-items
Align All Items Vertically using align-items
Divide the Grid Into an Area Template
Place Items in Grid Areas Using the grid-area Property
Use grid-area Without Creating an Areas Template
Reduce Repetition Using the repeat Function
Limit Item Size Using the minmax Function
Create Flexible Layouts Using auto-fill
Create Flexible Layouts Using auto-fit
Use Media Queries to Create Responsive Layouts
Create Grids within Grids
Comment Your JavaScript Code
Declare JavaScript Variables
Storing Values with the Assignment Operator
Assigning the Value of One Variable to Another
Initializing Variables with the Assignment Operator
Declare String Variables
Understanding Uninitialized Variables
Understanding Case Sensitivity in Variables
Explore Differences Between the var and let Keywords
Declare a Read-Only Variable with the const Keyword
Add Two Numbers with JavaScript
Subtract One Number from Another with JavaScript
Multiply Two Numbers with JavaScript
Divide One Number by Another with JavaScript
Increment a Number with JavaScript
Decrement a Number with JavaScript
Create Decimal Numbers with JavaScript
Multiply Two Decimals with JavaScript
Divide One Decimal by Another with JavaScript
Finding a Remainder in JavaScript
Compound Assignment With Augmented Addition
Compound Assignment With Augmented Subtraction
Compound Assignment With Augmented Multiplication
Compound Assignment With Augmented Division
Escaping Literal Quotes in Strings
Quoting Strings with Single Quotes
Escape Sequences in Strings
Concatenating Strings with Plus Operator
Concatenating Strings with the Plus Equals Operator
Constructing Strings with Variables
Appending Variables to Strings
Find the Length of a String
Use Bracket Notation to Find the First Character in a String
Understand String Immutability
Use Bracket Notation to Find the Nth Character in a String
Use Bracket Notation to Find the Last Character in a String
Use Bracket Notation to Find the Nth-to-Last Character in a String
Word Blanks
Store Multiple Values in one Variable using JavaScript Arrays
Nest one Array within Another Array
Access Array Data with Indexes
Modify Array Data With Indexes
Access Multi-Dimensional Arrays With Indexes
Manipulate Arrays With push Method
Manipulate Arrays With pop Method
Manipulate Arrays With shift Method
Manipulate Arrays With unshift Method
Shopping List
Write Reusable JavaScript with Functions
Passing Values to Functions with Arguments
Return a Value from a Function with Return
Global Scope and Functions
Local Scope and Functions
Global vs. Local Scope in Functions
Understanding Undefined Value returned from a Function
Assignment with a Returned Value
Stand in Line
Understanding Boolean Values
Use Conditional Logic with If Statements
Comparison with the Equality Operator
Comparison with the Strict Equality Operator
Practice comparing different values
Comparison with the Inequality Operator
Comparison with the Strict Inequality Operator
Comparison with the Greater Than Operator
Comparison with the Greater Than Or Equal To Operator
Comparison with the Less Than Operator
Comparison with the Less Than Or Equal To Operator
Comparisons with the Logical And Operator
Comparisons with the Logical Or Operator
Introducing Else Statements
Introducing Else If Statements
Logical Order in If Else Statements
Chaining If Else Statements
Golf Code
Selecting from Many Options with Switch Statements
Adding a Default Option in Switch Statements
Multiple Identical Options in Switch Statements
Replacing If Else Chains with Switch
Returning Boolean Values from Functions
Return Early Pattern for Functions
Counting Cards
Build JavaScript Objects
Accessing Object Properties with Dot Notation
Accessing Object Properties with Bracket Notation
Accessing Object Properties with Variables
Updating Object Properties
Add New Properties to a JavaScript Object
Delete Properties from a JavaScript Object
Using Objects for Lookups
Testing Objects for Properties
Manipulating Complex Objects
Accessing Nested Objects
Accessing Nested Arrays
Record Collection
Iterate with JavaScript While Loops
Iterate with JavaScript For Loops
Iterate Odd Numbers With a For Loop
Count Backwards With a For Loop
Iterate Through an Array with a For Loop
Nesting For Loops
Iterate with JavaScript Do...While Loops
Replace Loops using Recursion
Profile Lookup
Generate Random Fractions with JavaScript
Generate Random Whole Numbers with JavaScript
Generate Random Whole Numbers within a Range
Use the parseInt Function
Use the parseInt Function with a Radix
Use the Conditional (Ternary) Operator
Use Multiple Conditional (Ternary) Operators
Use Recursion to Create a Countdown
Use Recursion to Create a Range of Numbers
Compare Scopes of the var and let Keywords
Mutate an Array Declared with const
Prevent Object Mutation
Use Arrow Functions to Write Concise Anonymous Functions
Write Arrow Functions with Parameters
Set Default Parameters for Your Functions
Use the Rest Parameter with Function Parameters
Use the Spread Operator to Evaluate Arrays In-Place
Use Destructuring Assignment to Extract Values from Objects
Use Destructuring Assignment to Assign Variables from Objects
Use Destructuring Assignment to Assign Variables from Nested Objects
Use Destructuring Assignment to Assign Variables from Arrays
Destructuring via rest elements
Use Destructuring Assignment to Pass an Object as a Function's Parameters
Create Strings using Template Literals
Write Concise Object Literal Declarations Using Object Property Shorthand
Write Concise Declarative Functions with ES6
Use class Syntax to Define a Constructor Function
Use getters and setters to Control Access to an Object
Create a Module Script
Use export to Share a Code Block
Reuse JavaScript Code Using import
Use * to Import Everything from a File
Create an Export Fallback with export default
Import a Default Export
Create a JavaScript Promise
Complete a Promise with resolve and reject
Handle a Fulfilled Promise with then
Handle a Rejected Promise with catch
Using the Test Method
Match Literal Strings
Match a Literal String with Different Possibilities
Ignore Case While Matching
Extract Matches
Find More Than the First Match
Match Anything with Wildcard Period
Match Single Character with Multiple Possibilities
Match Letters of the Alphabet
Match Numbers and Letters of the Alphabet
Match Single Characters Not Specified
Match Characters that Occur One or More Times
Match Characters that Occur Zero or More Times
Find Characters with Lazy Matching
Find One or More Criminals in a Hunt
Match Beginning String Patterns
Match Ending String Patterns
Match All Letters and Numbers
Match Everything But Letters and Numbers
Match All Numbers
Match All Non-Numbers
Restrict Possible Usernames
Match Whitespace
Match Non-Whitespace Characters
Specify Upper and Lower Number of Matches
Specify Only the Lower Number of Matches
Specify Exact Number of Matches
Check for All or None
Positive and Negative Lookahead
Check For Mixed Grouping of Characters
Reuse Patterns Using Capture Groups
Use Capture Groups to Search and Replace
Remove Whitespace from Start and End
Use the JavaScript Console to Check the Value of a Variable
Understanding the Differences between the freeCodeCamp and Browser Console
Use typeof to Check the Type of a Variable
Catch Misspelled Variable and Function Names
Catch Unclosed Parentheses, Brackets, Braces and Quotes
Catch Mixed Usage of Single and Double Quotes
Catch Use of Assignment Operator Instead of Equality Operator
Catch Missing Open and Closing Parenthesis After a Function Call
Catch Arguments Passed in the Wrong Order When Calling a Function
Catch Off By One Errors When Using Indexing
Use Caution When Reinitializing Variables Inside a Loop
Prevent Infinite Loops with a Valid Terminal Condition
Use an Array to Store a Collection of Data
Access an Array's Contents Using Bracket Notation
Add Items to an Array with push() and unshift()
Remove Items from an Array with pop() and shift()
Remove Items Using splice()
Add Items Using splice()
Copy Array Items Using slice()
Copy an Array with the Spread Operator
Combine Arrays with the Spread Operator
Check For The Presence of an Element With indexOf()
Iterate Through All an Array's Items Using For Loops
Create complex multi-dimensional arrays
Add Key-Value Pairs to JavaScript Objects
Modify an Object Nested Within an Object
Access Property Names with Bracket Notation
Use the delete Keyword to Remove Object Properties
Check if an Object has a Property
Iterate Through the Keys of an Object with a for...in Statement
Generate an Array of All Object Keys with Object.keys()
Modify an Array Stored in an Object
Convert Celsius to Fahrenheit
Reverse a String
Factorialize a Number
Find the Longest Word in a String
Return Largest Numbers in Arrays
Confirm the Ending
Repeat a String Repeat a String
Truncate a String
Finders Keepers
Boo who
Title Case a Sentence
Slice and Splice
Falsy Bouncer
Where do I Belong
Mutations
Chunky Monkey
Create a Basic JavaScript Object
Use Dot Notation to Access the Properties of an Object
Create a Method on an Object
Make Code More Reusable with the this Keyword
Define a Constructor Function
Use a Constructor to Create Objects
Extend Constructors to Receive Arguments
Verify an Object's Constructor with instanceof
Understand Own Properties
Use Prototype Properties to Reduce Duplicate Code
Iterate Over All Properties
Understand the Constructor Property
Change the Prototype to a New Object
Remember to Set the Constructor Property when Changing the Prototype
Understand Where an Object’s Prototype Comes From
Understand the Prototype Chain
Use Inheritance So You Don't Repeat Yourself
Inherit Behaviors from a Supertype
Set the Child's Prototype to an Instance of the Parent
Reset an Inherited Constructor Property
Add Methods After Inheritance
Override Inherited Methods
Use a Mixin to Add Common Behavior Between Unrelated Objects
Use Closure to Protect Properties Within an Object from Being Modified Externally
Understand the Immediately Invoked Function Expression (IIFE)
Use an IIFE to Create a Module
Learn About Functional Programming
Understand Functional Programming Terminology
Understand the Hazards of Using Imperative Code
Avoid Mutations and Side Effects Using Functional Programming
Pass Arguments to Avoid External Dependence in a Function
Refactor Global Variables Out of Functions
Use the map Method to Extract Data from an Array
Implement map on a Prototype
Use the filter Method to Extract Data from an Array
Implement the filter Method on a Prototype
Return Part of an Array Using the slice Method
Remove Elements from an Array Using slice Instead of splice
Combine Two Arrays Using the concat Method
Add Elements to the End of an Array Using concat Instead of push
Use the reduce Method to Analyze Data
Use Higher-Order Functions map, filter, or reduce to Solve a Complex Problem
Sort an Array Alphabetically using the sort Method
Return a Sorted Array Without Changing the Original Array
Split a String into an Array Using the split Method
Combine an Array into a String Using the join Method
Apply Functional Programming to Convert Strings to URL Slugs
Use the every Method to Check that Every Element in an Array Meets a Criteria
Use the some Method to Check that Any Elements in an Array Meet a Criteria
Introduction to Currying and Partial Application
Sum All Numbers in a Range
Diff Two Arrays
Seek and Destroy
Wherefore art thou
Spinal Tap Case
Pig Latin
Search and Replace
DNA Pairing
Missing letters
Sorted Union
Convert HTML Entities
Sum All Odd Fibonacci Numbers
Sum All Primes
Smallest Common Multiple
Drop it
Steamroller
Binary Agents
Everything Be True
Arguments Optional
Make a Person
Map the Debris
Palindrome Checker
Roman Numeral Converter
Caesars Cipher
Telephone Number Validator
Cash Register
Introduction: Why Program?
Introduction: Hardware Architecture
Introduction: Python as a Language
Introduction: Elements of Python
Variables, Expressions, and Statements
Intermediate Expressions
Conditional Execution
More Conditional Structures
Python Functions
Build your own Functions
Loops and Iterations
Iterations: Definite Loops
Iterations: Loop Idioms
Iterations: More Patterns
Strings in Python
Intermediate Strings
Reading Files
Files as a Sequence
Python Lists
Working with Lists
Strings and Lists
Python Dictionaries
Dictionaries: Common Applications
Dictionaries and Loops
The Tuples Collection
Comparing and Sorting Tuples
Regular Expressions
Regular Expressions: Matching and Extracting Data
Regular Expressions: Practical Applications
Networking with Python
Networking Protocol
Networking: Write a Web Browser
Networking: Text Processing
Networking: Using urllib in Python
Networking: Web Scraping with Python
Using Web Services
Web Services: XML
Web Services: XML Schema
Web Services: JSON
Web Services: Service Oriented Approach
Web Services: APIs
Web Services: API Rate Limiting and Security
Python Objects
Objects: A Sample Class
Object Lifecycle
Objects: Inheritance
Relational Databases and SQLite
Make a Relational Database
Relational Database Design
Representing Relationships in a Relational Database
Relational Databases: Relationship Building
Relational Databases: Join Operation
Relational Databases: Many-to-many Relationships
Visualizing Data with Python
Data Visualization: Page Rank
Data Visualization: Mailing Lists
Write Your First C# Code
Store and Retrieve Data Using Literal and Variable Values in C#
Perform Basic String Formatting in C#
Perform Basic Operations on Numbers in C#
Guided Project - Calculate and Print Student Grades
Guided Project - Calculate Final GPA
Trophy - Write Your First Code Using C#
Install and Configure Visual Studio Code
Call Methods From the .NET Class Library Using C#
Add Decision Logic to Your Code Using if, else, and else if statements in C#
Store and Iterate Through Sequences of Data Using Arrays and the foreach Statement in C#
Create Readable Code with Conventions, Whitespace, and Comments in C#
Guided Project - Develop foreach and if-elseif-else Structures to Process Array Data in C#
Challenge Project - Develop foreach and if-elseif-else Structures to Process Array Data in C#
Trophy - Create and Run Simple C# Console Applications
Evaluate Boolean Expressions to Make Decisions in C#
Control Variable Scope and Logic Using Code Blocks in C#
Branch the Flow of Code Using the switch-case Construct in C#
Iterate Through a Code Block Using the for Statement in C#
Add Looping Logic to Your Code Using the do-while and while Statements in C#
Guided Project - Develop Conditional Branching and Looping Structures in C#
Challenge Project - Develop Branching and Looping Structures in C#
Trophy - Add Logic to C# Console Applications
Choose the Correct Data Type in Your C# Code
Convert Data Types Using Casting and Conversion Techniques in C#
Perform Operations on Arrays Using Helper Methods in C#
Format Alphanumeric Data for Presentation in C#
Modify the Content of Strings Using Built-In String Data Type Methods in C#
Guided Project - Work with Variable Data in C#
Challenge Project - Work with Variable Data in C#
Trophy - Work with Variable Data in C# Console Applications
Write Your First C# Method
Create C# Methods with Parameters
Create C# Methods that Return Values
Guided Project - Plan a Petting Zoo Visit
Challenge Project - Create a Mini-Game
Trophy - Create Methods in C# Console Applications
Review the Principles of Code Debugging and Exception Handling
Implement the Visual Studio Code Debugging Tools for C#
Implement Exception Handling in C# Console Applications
Create and Throw Exceptions in C# Console Applications
Guided Project - Debug and Handle Exceptions in a C# Console Application Using Visual Studio Code
Challenge Project - Debug a C# Console Application Using Visual Studio Code
Trophy - Debug C# Console Applications
Foundational C# with Microsoft Certification Exam