*** WSDL stands for Web Services Description Language. A WSDL file is an XML document that describes a Web service. It specifies the location of the service and the operations (or methods) the service exposes. For more information about WSDL, refer to the [WSDL specification](http://www.w3.org/TR/wsdl), or read the [WSDL tutorial](http://www.w3schools.com/wsdl/) *** **References**: - [Spring WS - Why Contract First?](https://docs.spring.io/spring-ws/docs/current/reference/html/#why-contract-first)