RabbitMQ is a message broker. The principal idea is pretty simple: it accepts and forwards messages. You can think about it as a post office: when you send mail to the post box you're pretty sure that Mr. Postman will eventually deliver the mail to your recipient. Using this metaphor RabbitMQ is a post box, a post office and a postman.

The major difference between RabbitMQ and the post office is the fact that it doesn't deal with paper, instead it accepts, stores and forwards binary blobs of data ‒ messages.

RabbitMQ, and messaging in general, uses some jargon.


  • Producing means nothing more than sending. A program that sends messages is a producer. We'll draw it like that, with "P": 
  • A queue is the name for a mailbox. It lives inside RabbitMQ. Although messages flow through RabbitMQ and your applications, they can be stored only inside a queue. A queue is not bound by any limits, it can store as many messages as you like ‒ it's essentially an infinite buffer. Many producers can send messages that go to one queue, many consumers can try to receive data from one queue. A queue will be drawn as like that, with its name above it: 
  • Consuming has a similar meaning to receiving. A consumer is a program that mostly waits to receive messages. On our drawings it's shown with "C":


Note that the producer, consumer, and broker do not have to reside on the same machine; indeed in most applications they don't.