Notes on Web Service
Soap is the communications protocol for XML Web services. SOAP is a specification that defines the XML format for messages—and that’s about it for the required parts of the spec. If you have a well-formed XML fragment enclosed in a couple of SOAP elements, you have a SOAP message. Simple isn’t it?
There are other parts of the SOAP specification that describe how to represent program data as XML and how to use SOAP to do Remote Procedure Calls. These optional parts of the specification are used to implement RPC-style applications where a SOAP message containing a callable function, and the parameters to pass to the function, is sent from the client, and the server returns a message with the results of the executed function.
WSDL is an XML format for describing network services as a set of endpoints operating on messages containing either document-oriented or procedure-oriented information
UDDI: Universal Discovery Description and Integration is the yellow pages of Web services
Source: http://msdn2.microsoft.com/en-us/library/ms996507.aspx
