Class Central

Rankings
Collections

Subjects

View all

Computer Science
Health & Medicine
Mathematics
Business
Humanities
Engineering
Science
Education & Teaching
Social Sciences
Art & Design
Artificial Intelligence
Data Science
Programming
Personal Development
Information Security (InfoSec)

View all Subjects

Universities
The Report

Courses from 1000+ universities

Rankings

Best Courses

Best of All Time
Best of the Year

Most Popular Courses

Most Popular of All Time
Most Popular of the Year

Collections

Computer Science

Algorithms and Data Structures
Internet of Things
Information Technology
Computer Networking
Machine Learning
DevOps
Deep Learning
Cryptography
Quantum Computing
Human-Computer Interaction (HCI)
Distributed Systems
Blockchain Development
Operating Systems
Computer Graphics
Automata Theory
Compilers
SCADA
Mainframe
Digital Image Processing
Computational Models
View all Computer Science

Health & Medicine

Nutrition & Wellness
Disease & Disorders
Public Health
Health Care
Nursing
Anatomy
Veterinary Science
Continuing Medical Education (CME)
Blood Pressure
Wellbeing
Women's Health
Dysphagia
Occupational Therapy
Hygiene
Healthcare Innovation
Music Therapy
Holistic Health
Ayurveda
Herbalism
Massage Therapy
View all Health & Medicine

Mathematics

Statistics & Probability
Foundations of Mathematics
Calculus
Discrete Mathematics
Trigonometry
Geometry
Algebra
Precalculus
Number Theory
Combinatorics
Mathematical logic
Linear Programming
Graph Theory
Set Theory
Group Theory
Differential Equations
Polynomials
Integration
Mathematical Analysis
Mathematical Thinking
View all Mathematics

Business

Management & Leadership
Finance
Entrepreneurship
Marketing
Strategic Management
Industry Specific
Business Intelligence
Accounting
Human Resources
Project Management
Sales
Design Thinking
Business Software
Customer Service
Nonprofit Management
Innovation
Operations Management
Corporate Governance
Business Plan
Business Proposal
View all Business

Humanities

History
Literature
Language Learning
Grammar & Writing
Philosophy
Religion
ESL
Culture
Sports
Journalism
Ethics
Linguistics
Food
Library Science
Reading
Crisis Management
Games
Emergency Management
Performing Arts
Religious Studies
View all Humanities

Engineering

Electrical Engineering
Mechanical Engineering
Civil Engineering
Robotics
Nanotechnology
GIS
Textiles
Manufacturing
BIM
CAD
Chemical Engineering
Energy Systems
Aerospace Engineering
Finite Element Analysis
Geotechnical Engineering
Reliability Engineering
Petroleum Engineering
Control Theory
Environmental Engineering
Energy Conversion
View all Engineering

Science

Chemistry
Physics
Environmental Science
Astronomy
Biology
Agriculture
Materials Science
Earth Science
Applied Science
Forensic Science
Meteorology
Horology
Paleontology
Fire Science
Sensory Science
Ergonomics
Physical Sciences
Complex Systems
Scientific Method
Medicine
View all Science

Education & Teaching

K12
Higher Education
STEM
Teacher Professional Development
Course Development
Online Education
Pedagogy
Social-emotional Learning (SEL)
Instructional Design
Homeschooling
Special Education
Adult Education
Course Design
Online Learning
Educational Technology
Curriculum Development
Next Generation Science Standards
Student-Centered Learning
Student Engagement
Classroom Management
View all Education & Teaching

Social Sciences

Sociology
Economics
Psychology
Anthropology
Political Science
Law
Urban Planning
Human Rights
Sustainability
Governance
Archaeology
Social Work
Early Childhood Development
Structural Equation Modeling
Cultural Studies
Research Methods
Community Engagement
Philanthropy
Behavioral Science
Media Studies
View all Social Sciences

Art & Design

Music
Digital Media
Visual Arts
Design & Creativity
Photography
Art Therapy
Art Composition
Character Design
Fashion Design
Inspiration
Golden Ratio
Pattern Design
Geometric Patterns
Copic Markers
Jewelry Design
Animal Illustration
Anime Drawing
Street Art
Observational Drawing
Greeting Cards
View all Art & Design

Artificial Intelligence

Computer Vision
Natural Language Processing (NLP)
Neural Networks
Autonomous Vehicles
Chatbot
IBM Watson
Generative AI
Intelligent Systems
Genetic Algorithms
Intelligence
Heuristics
Ontology
Collective Intelligence
Autonomous Agents
Constraint Programming
AI Ethics
Semantics
Computational Linguistics
Computational Creativity
Evolutionary Algorithms
View all Artificial Intelligence

Data Science

Bioinformatics
Big Data
Data Mining
Data Analysis
Data Visualization
Jupyter Notebooks
Process Mining
Stata
Text Mining
Social Network Analysis
Computational Analysis
Data Collection
Information Retrieval
Data Processing
Data Wrangling
Data Extraction
Data Manipulation
Monte Carlo Simulation
Network Analysis
Data Preparation
View all Data Science

Programming

Mobile Development
Web Development
Databases
Game Development
Programming Languages
Software Development
Cloud Computing
Domain-Specific Languages (DSL)
Hardware Description Languages (HDL)
Aspect-oriented programming
Object-oriented programming
Visual Programming
Competitive Programming
Database Programming
Generic Programming
Programming Language Development
Leetcode
GNU Toolchain
Windsurf
Vibe Coding
View all Programming

Personal Development

Communication Skills
Career Development
Self Improvement
Presentation Skills
Resilience
Self-Control
Creativity
Gratitude
Growth Mindset
Self-Assessment
Survival Skills
Sleep Improvement
Career Planning
Empowerment
Generosity
Personal Growth
Courage
Humility
Social Skills
Dog Training
View all Personal Development

Information Security (InfoSec)

Cybersecurity
Network Security
Ethical Hacking
Digital Forensics
Reverse Engineering
Penetration Testing
Malware Analysis
DevSecOps
OSINT (Open Source Intelligence)
Threat Intelligence
Red Team
Blue Team
View all Information Security (InfoSec)

The Series Finale of Online Education: Coursera Acquires Udemy

$7.2 billion in combined revenue since 2020. $8 billion in lost market value. This merger marks the end of an era in online education.

Dhawal Shah Feb 11, 2026

Latest

9 Best Delphi Courses for 2026: Effortless Cross-Platform GUIs
8 Best Anthropology Courses for 2026: Understanding Cultures
10 Best CSS Animation Courses for 2026: Bring HTML to Life
9 Best Bug Bounty Courses for 2026: Ethical Hacking, Safer Web
UpGrad to Acquire Unacademy, Once a $3.5B Unicorn, in a Share Swap Deal

Write for The Report

Visit The Report

600 Free Google Certifications
Trending

Most common

Popular subjects

Machine Learning
26,564 courses
Python
13,391 courses
Microsoft Excel
2,254 courses

Popular courses

Intelligenza Artificiale
University of Urbino
Python for Data Science
University of California, San Diego
Introduction to Philosophy
University of Edinburgh

Organize and share your learning with Class Central Lists.

View our Lists Showcase

Sign up

Log in or Sign up

Log in
Sign up

Subjects
Science
Physics
Optics
Refraction

Free Online

Refraction Courses and Certifications

Master light behavior through hands-on experiments with reflection, refraction, and Snell's Law to solve real-world optics problems. Learn from physics educators on YouTube, edX, and MIT OpenCourseWare, covering everything from basic wave theory to advanced applications in engineering and technology.

51 courses

Related Subjects

Optics Courses
Lenses Courses
Optical Physics Courses
Dispersion Courses
Spectroscopy Courses
Fiber Optics Courses

Showing 51 courses

Sort by Relevancy

Filter by

Filters

1. With certificate (6)
2. Free course (51)
3. With free certificate (1)
4. University course only (8)
Level
1. Intermediate (22)
2. Advanced (16)
3. Beginner (9)
Duration
1. < 30 mins (17)
2. 30 - 60 mins (7)
3. 1 - 2 hours (11)
4. 2 - 5 hours (3)
5. 5 - 10 hours (3)
6. 10+ hours (4)
Language
1. English (50)
2. Chinese (2)
3. Spanish (1)

Gautam Varde
Ray Optics - Complete Chapter for Class 12 Physics Board Exam, JEE, and NEET

Master ray optics fundamentals including reflection, refraction, lenses, mirrors, and optical instruments for Class 12 Physics, JEE, and NEET exams.
- YouTube
- 2 hours 27 minutes
- On-Demand
- Free Video
$Reflection and Refraction in General Physics - Lesson 22.1$

Chad's Prep
Reflection and Refraction in General Physics - Lesson 22.1

Explore reflection, refraction, and related optical phenomena. Master key concepts like Snell's Law, total internal reflection, and dispersion through detailed explanations and practice problems.
- YouTube
- 34 minutes
- On-Demand
- Free Video
$College Physics: Reflection and Refraction of Light - Chapter 23 Summary$

Dot Physics
College Physics: Reflection and Refraction of Light - Chapter 23 Summary

Explore key concepts of light behavior including reflection, refraction, and mirror types. Learn to analyze light ray diagrams and understand optical phenomena.
- YouTube
- 24 minutes
- On-Demand
- Free Video
$Optics Applications - Reflection, Refraction, and Pinholes$

Dot Physics
Optics Applications - Reflection, Refraction, and Pinholes

Explore optics applications through hands-on demos covering parallax, refraction, reflection, and pinhole cameras. Gain practical insights into fundamental optical principles.
- YouTube
- 19 minutes
- On-Demand
- Free Video
$Refraction of Light Waves - Solving Problems with Refractive Index$

Excellence Academy
Refraction of Light Waves - Solving Problems with Refractive Index

Master the principles of light wave refraction and learn to solve problems using Snell's law, understanding refractive indices and practical applications in physics.
- YouTube
- 11 minutes
- On-Demand
- Free Video
$Refraction of Light at a Plane Surface - Definition, Laws and Problem Solving$

Excellence Academy
Refraction of Light at a Plane Surface - Definition, Laws and Problem Solving

Master the principles of light refraction through plane surfaces, including fundamental laws, practical applications, and problem-solving techniques with detailed solutions.
- YouTube
- 28 minutes
- On-Demand
- Free Video
$Optics: Refraction, Reflection, and Snell's Law - Lecture 2$

CoA Physics
Optics: Refraction, Reflection, and Snell's Law - Lecture 2

Master the principles of optical physics through comprehensive coverage of refraction, reflection, Snell's Law, and practical problem-solving in ray optics.
- YouTube
- 1 hour 15 minutes
- On-Demand
- Free Video
Physics Fundamentals: Oscillations and Waves

We will study the wide variety of wave phenomena observed in nature.
- edX
- 5 weeks, 3-4 hours a week
- On-Demand
- Free Online Course (Audit)
Physics Fundamentals: Oscillations and Waves

Explore wave physics fundamentals including oscillations, propagation phenomena, reflection, refraction, diffraction, and the Doppler effect through comprehensive analysis.
- Coursera
- 11 hours 47 minutes
- On-Demand
- Paid Course
Optics

Comprehensive exploration of optical science, covering geometrical and wave optics. Delves into ray-tracing, aberrations, lens design, electrodynamics, polarization, diffraction, and image formation. Emphasizes analytical and numerical tools for optical…
- MIT OpenCourseWare
- On-Demand
- Free Online Course
Physics Online
Everything About Waves - A Level Physics

Master wave physics fundamentals including electromagnetic waves, interference, diffraction, standing waves, and the Doppler effect through comprehensive A Level content.
- YouTube
- 1 hour 48 minutes
- On-Demand
- Free Video
Physics Online
The Essentials for GCSE Physics

Master essential physics skills including equipment use, units, data plotting, and calculator techniques for GCSE success.
- YouTube
- 43 minutes
- On-Demand
- Free Video
$Optical Meta-Materials - Negative Refraction, Super-lens and Plasmon Laser$

BIMSA
Optical Meta-Materials - Negative Refraction, Super-lens and Plasmon Laser

Discover optical meta-materials and their revolutionary applications in negative refraction, super-lens technology, and plasmon lasers with leading expert Xiang Zhang.
- YouTube
- 1 hour 5 minutes
- On-Demand
- Free Video
Optics Theory and Methods
1 review

Master the fundamentals of ophthalmic conditions and their treatments, from myopia and hyperopia to astigmatism and anisometropia, while developing practical clinical skills for vision health care.
- XuetangX
- On-Demand
- Free Online Course
IIT Kharagpur; NPTEL
Experimental Physics - II

Explore fundamental optical phenomena through hands-on experiments in interference, diffraction, polarization, and quantum physics. Gain practical skills in using spectrometers and other essential apparatus.
- Swayam
- 12 weeks
- On-Demand
- Free Online Course

Browse by subject

Computer Science
Psychology
Cybersecurity
Health
Law
Accounting
Web Development

Browse by provider

Coursera
Udacity
edX
Noble Desktop
freeCodeCamp
CodeSignal
Boot.dev

Browse by university

Harvard
MIT
Georgia Tech
University of Michigan
Purdue University
Duke University
IIT Madras

Browse by institution

Google
Microsoft
IBM
Amazon
Linux Foundation
British Council
Salesforce

Best Online Courses of All Time
Best Online Courses of the Year
Most Popular Courses of All Time
Most Popular Courses of the Year
100 Top FREE Coursera Courses of All Time
Best Courses Guides
Free Printable Study Calendar

The Report by Class Central RSS Feed

The "New Normal" that Wasn't
DDoS Attack on Class Central
2000+ Online Degrees in India
Harvard's CS50 Free Certificate Guide
How Open University Works

Free Certificates & Courses

450+ Free Google Certificates
10000+ Free Courses from Tech Giants
300+ Free Coursera Courses
Ivy League Online Courses
200+ Free Writing Online Courses

About Class Central

Class Central aggregates courses from many providers to help you find the best courses on almost any subject, wherever they exist.

Facebook
Twitter
LinkedIn
YouTube
Bluesky

Class Central © 2011-2026 Privacy Policy

About Us
Join Us
Write for Us
Help Center
Contact Us

Share

Facebook
Twitter
Bluesky
Email

Never Stop Learning.

Get personalized course recommendations, track subjects and courses with reminders, and more.

Sign up for free

Someone learning on their laptop while sitting on the floor.