The wwf processing come from document processing, where documents need to go from place to other for approval or review. but the notion of executing a specific set of tasks, coupled with decision making(such as approved or not approved), is something we can generalize. in fact, if you've ever written a piece of software that processed information, made decisions based on system inputs, and look into account the rules and partices of system in which the software executed, I'd argue that you've wrriten workflow software.
Sequential Workflow-- Designer Exist in VS.net 2005 with framework 3.0 or 3.5

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