Web Service Description Language (WSDL) is a W3C specification which defines XML grammar for describing Web Services.
• XML Grammar describes details such as:-
• Where we can find the Web Service (its URI)?
• What are the methods and properties that service supports?
• Data type support. Supported protocols In short its a bible of what the webservice can do. Clients can consume this WSDL and build proxy objects that clients use to communicate with the Web Services.