Workflow Markup Overview
Workflow markup, which is based on extensible Application Markup Language (XAML), enables developers and designers to model business logic declaratively and separate it from lower-level implementation details that are modeled by code-beside files. Because workflows can be modeled declaratively, it is possible to activate a workflow by directly loading a workflow markup file into the workflow runtime engine at run time.
For more information about workflow markup, see Using Workflow Markup.