Akka Actor Systems

Akka is a JVM toolkit for building concurrent, distributed, and fault-tolerant systems using the actor model. Actors are lightweight entities that process messages sequentially. Instead of threads and locks, you send messages between actors; Akka handles concurrency via thread pools. Core features: message passing, location transparency (actors can be local or remote), supervisors (fault recovery), and clustering (multi-machine coordination). Akka shines when you need millions of concurrent actors and built-in fault tolerance.