What is Message Oriented Middleware (MOM)?
MOM permits general purpose messages to be exchanged in a Client/Server system using message queues. Applications communicate over networks by just putting messages in the queues and getting messages from queues. It typically gives a very simple high level APIs to its services.
MOM's messaging and queuing permits clients and servers to communicate across a network without being linked by a dedicated, private, logical connection. The clients and server can run at various times. It is a post-office like metaphor.