MiddleWare which takes in messages, queues them, and sends them out one at a time.

Essential for systems which require transactional integrity.

''What are typical uses for them, and how are they allegedly better than RDBMS or web services?''

* Not qualified for a complete answer to your question, however the ability of the middleware for handling async messaging (contrast Corba  at CommonObjectRequestBrokerArchitecture) is important, I think. See walso EnterpriseServiceBus

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Feb2004. Update from 2004. MicrosoftIndigo is shaping up to be an important product to watch, but that may be determined more by the adoption of the server versions of WindowsLonghorn, which can be years away.

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	* MessageQueuingArchitectures

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CategoryCommunicationProtocol