 A number of distinct interoperability scenarios can then be constructed by reference to such interfaces, identifying different levels of functional conformance as appropriate to the range of products in the market.XPDL is an XML based language for describing a process definition, developed by the WfMC.The goal of XPDL is to store and exchange the process diagram, allowing one tool to model a process diagram, another to read the diagram and edit, yet another to "run" the process model on an XPDL-compliant BPM engine, and so on.