Introduction

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

Producer

Producing means nothing more than sending. A program that sends messages is a producer.

 

A queue is the name for a post box which lives inside RabbitMQ. Although messages flow through RabbitMQ and your applications, they can only be stored inside a queue. A queue is only bound by the host's memory & disk limits, it's essentially a large message buffer. Many producers can send messages that go to one queue, and many consumers can try to receive data from one queue. This is how we represent a queue: 

Consuming has a similar meaning to receiving. A consumer is a program that mostly waits to receive messages: 

Note that the producer, consumer, and broker do not have to reside on the same host; indeed in most applications they don't. An application can be both a producer and consumer, too.