State Machine Activities in WF

.NET Framework (current version)

.NET Framework 4.5 provides several system-provided activities and activity designers for creating state machine workflows.

StateMachineExecutes contained activities using the familiar state machine paradigm.
StateRepresents a state in a state machine.
FinalStateRepresents a terminating state in a state machine. FinalState is an activity designer that when used creates a State preconfigured as a terminating state. For more information, see FinalState Activity Designer.
TransitionRepresents the transition between two states. There is no Toolbox item for Transition; transitions are created on the workflow designer by dragging and dropping a line between two states, or by dropping a state on the triangles that appear when one state is hovered over another. For more information, see Transition Activity Designer.

Getting Started Tutorial