Message queuing stores tasks or messages until a receiving service is ready to process them.
Work waits in line
A queue lets one component place a message while another processes it later. This absorbs bursts and separates the speed of a producer from the availability of a worker.
Queues trade immediacy for resilience
Acknowledgements, visibility timeouts, dead-letter handling, and retry limits determine what happens to failed work. Monitoring queue age is often more useful than counting messages alone.