What is a message broker?

A message broker is a component of software architecture that facilitates the transfer of messages between different applications or services. It acts as an intermediary, receiving messages from senders and delivering them to recipients, often with guarantees of delivery, routing, and buffering.

Main functions of a message broker:

• Asynchronous communication between systems
• Message queues for load balancing
• Guaranteed delivery and resend on errors
• Support for various protocols and message formats

Examples of message brokers include RabbitMQ, Apache Kafka, ActiveMQ. They enable the construction of distributed systems with high reliability and scalability.