Web Services Description Language
A WSDL description of a service tells us, in a machine-understandable way, the interface to the service, the data types it uses, and where the service is located.
Has 6 major elements
definitions – defines the name of the web service
types – describes all the data types that will be transmitted
message – defines the name of the message that will be transmitted
portType – defines the operations which operates on the input and output messages
binding – defines how the message will be transmitted,binding the service.
service – defines where the service is located