Websphere MQ offers a means to connect each piece of your business software together, creating a seamless, powerful messaging system that can communicate between disparate computers, utilizing different operating systems and even housed in different locations.
The IBM Websphere MQ range of products provides application programming services that enable application programs to communicate with each other using messages and queues. This form of communication is referred to as commercial messaging. It provides assured, once-only delivery of messages. Using MQSeries means that you can separate application programs, so that the program sending a message can continue processing without having to wait for a reply from the receiver. If the receiver or the communication channel to it is temporarily unavailable, the message can be forwarded at a later time. MQSeries also provides mechanisms for providing acknowledgements of messages received.
The applications are written using a common programming interface known as the Message Queue Interface (MQI), so that applications developed on one platform can be transferred to another. (WebSphere Desc. courtesy of IBM at http://www-3.ibm.com/software/integration/wmq/about/).