What is Publish/Subscribe?

Publish/Subscribe (often shortened to Pub/Sub) is a messaging pattern where senders of messages, called publishers, do not program the messages to be sent directly to specific receivers, called subscribers. Instead, published messages are categorized into channels or topics, and subscribers express interest in one or more channels or topics and only receive messages that are of interest, without knowledge of who the publishers are. This decoupling of publishers and subscribers allows for greater scalability and flexibility in distributed systems. Common use cases include event notification, real-time data streaming, and asynchronous task processing.