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SOAP is a Microsoft/Lotus/IBM-developed protocol for exchanging information in distributed environments. It provides a common message-passing protocol that uses HTTP to carry messages that are formatted in XML (Extensible Markup Language). One of the key objectives of SOAP is to provide a way for business applications running on the Internet or in other distributed environments to talk to each other using XML as the basis for information exchange. Programs on different computers can connect without regard to operating system or platform. Microsoft sees SOAP as a way for Web sites to provide application services via SOAP-based interfaces. SOAP is now a W3C specification.