Message Queue
In plain terms
A buffer that holds messages between sender and receiver.
Going deeper
A message queue decouples producers and consumers by storing messages until they're processed, enabling async, reliable communication. Senders and receivers needn't be online together.
Under the hood
Provides buffering, retries, and load leveling; ordering and delivery guarantees vary by system.
Examples
RabbitMQ, AWS SQS, Kafka, task queues, async processing, decoupling.
Think of it like...
Like a mailbox holding letters until the recipient is ready to read them.