ActiveMQ
ActiveMQ is an open-source message broker that implements the Java Message Service (JMS) API, enabling asynchronous communication between distributed systems. It supports multiple protocols like AMQP, MQTT, and STOMP, and provides features such as message persistence, clustering, and high availability. It is widely used for building scalable and reliable enterprise messaging applications.
Developers should learn ActiveMQ when building distributed systems that require reliable, asynchronous messaging, such as microservices architectures, event-driven applications, or IoT platforms. It is particularly useful in Java-based environments due to its JMS compliance, and for scenarios needing message queuing, publish-subscribe patterns, or integration with legacy systems.