Message queue
Also called: Queue, Message broker
A buffer where one part of a system leaves work as messages and another part picks them up later.
Definition
A queue decouples the producer of work from the consumer: the request that uploads a photo returns immediately, and workers create thumbnails and update feeds when they get to it. Queues absorb traffic spikes, survive a slow or failed consumer, and let each side scale separately. Kafka, RabbitMQ, SQS and Redis streams are common choices.
In practice
A checkout service publishes "order placed", and separate workers send the email and update the warehouse.
Learn it in context
Lessons that use this term.