Introduction to WSDL

Web Service Description Language (WSDL) is an XML language that contains information about the interface, semantics and "administrivia" of a call to a Web service.

Once you have developed a Web service, you publish its description and a link to it in a UDDI (Universal Description, Discovery and Integration) repository so that potential users can find it. When someone thinks they want to use your service, they request your WSDL file in order to find out the location of the service, the function calls and how to access them. Then they use this information in your WSDL file to form a SOAP (Simple Object Access Protocol) request to your computer.