An operation describes an interaction between a web service consumer and a web service provider. This requires an operation to exchange a set of input and output messages. Input and output messages are specified using the input and output child elements of the operation element.

In the syntax for the operation element, OperationName is the name of the operation and inputMsg and outputMsg are values for the message attribute. These values are derived from the name attribute of the message element.

In the code example, getBook is the name of the operation. The values getBookRequest and getBookResponse are names defined in the message element.