Explore the fascinating world of active matter in this 42-minute lecture from the Instituto de Física Interdisciplinar y Sistemas Complejos (IFISC). Delve into the intricacies of cluster formation, order, and aggregation processes, examining various classes of active phase separation. Gain insights into the complex behaviors exhibited by self-propelled particles and their collective dynamics. Discover how these phenomena relate to real-world systems in biology, physics, and materials science. Enhance your understanding of non-equilibrium physics and emergent properties in active systems through this comprehensive presentation.