Multi-Agent Pathfinding (MAPF) is the problem of planning the trajectory of many agents, from their start location to their respective destination, while sharing the same environment and avoiding collisions. It is part of the AI field of Planning and unifies concepts of Applied Mathematics, Computer Science, and Robotics. MAPF started being studied during the last decades of the 20th century, but only after 2000 some practical solutions were presented. Over the last few years, it acquired more interest, especially from the application point of view, thanks to the development of advanced Robotics Systems. Well-known accomplishments include warehouse automation in Industry 4.0.