Activity diagrams<\/b>\u00a0are graphical representations of\u00a0workflows<\/a>\u00a0of stepwise activities and actions with support for choice, iteration and concurrency. In the\u00a0Unified Modeling Language<\/a>, activity diagrams are intended to model both computational and organizational processes (i.e., workflows), as well as the data flows intersecting with the related activities. Although activity diagrams primarily show the overall flow of control, they can also include elements showing the flow of data between activities through one or more data stores.<\/p>\n Activity diagrams are constructed from a limited number of shapes, connected with arrows. The most important shape types:<\/p>\n Arrows run from the start towards the end and represent the order in which activities happen.<\/p>\n Activity diagrams can be regarded as a form of a structured\u00a0flowchart<\/a>\u00a0combined with a traditional data flow diagram. Typical flowchart techniques lack constructs for expressing concurrency. However, the join and split symbols in activity diagrams only resolve this for simple cases; the meaning of the model is not clear when they are arbitrarily combined with decisions or loops.<\/p>\nConstruction<\/span><\/h4>\n
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