A single web service may communicate with multiple clients at the same time, and it may communicate with each client multiple times. In order for the web service or control to track data for the client during asynchronous communication, it must have a way to remember which data belongs to which client and to keep track of where each client is in the process of operations. In Workshop, you use conversations to uniquely identify a given communication between a client and your application and to maintain state between operations.
The following topics will explain how to design and develop conversational web services:
WebLogic Server documentation: Creating Conversational Web Services