A message exchange is also referred to as an operation.
Operations are what consumers care about most since they're the focal point of interacting with the service (see Figure 2).
The Web Services Description Language (WSDL) provides an XML grammar for describing these details.
WSDL picks up where XML Schema left off by providing a way to group messages into operations and operations into interfaces.
Whenever I approach a new Web service, I first inspect its list of supported operations to get an overall feel for what it offers.
Figure 2: Messages and operations It's common for developers to group related operations into interfaces.
Figure 4: WS-I Basic Profile 1.0 technologies Since WSDL is a machine-readable language (e.g., it's just an XML file), tools and infrastructure can be easily built around it.
A binding specifies the concrete details of what goes on the wire by outlining how to use an interface with a particular communication protocol. Check out Understanding SOAP for more background on these concepts.(24 printed pages) Overview WSDL Basics Types Messages Interfaces (port Types) Bindings Services WSDL Editors Where Are We?References Appendix: WSDL XML makes it possible for developers to expose valuable resources in a highly interoperable fashion, where a resource is any type of application or data store used within an organization.Aaron Skonnard Northface University October 2003 Applies to: Web Services Web Services Description Language (WSDL) 1.1 WS-I Basic Profile Version 1.0 XML Messaging XML Schema Summary: See the importance of WSDL in the overall Web services architecture, as it describes the complete contract for application communication.Make Web services widely approachable by using WSDL definitions to generate code that knows precisely how to interact with the Web service described, and hides tedious details in sending and receiving SOAP messages over different protocols.