An Action Diagram is a structured means of documenting a module or subsystem, based on the use of square brackets alongside a textual explanation. By using different-shaped brackets, it is possible to denote the standard structures incorporated in modular software (or modular design), such as: Loop, Sequence, If etc. This method is particularly suitable for documenting modules (Component 2.7 of the System Component Tree - SCT). It may also be employed to describe processes and main modules (Component 2.5 of the SCT) and subsystems (Component 2.3). An Action Diagram belongs to the family of structured software and design techniques (such as PDL). Its substitute in the UML (Object Oriented) notation is Sequence Diagram

• See Sequence Diagram

• See also Component 2.7: Modules (Programs) in the Universal SCT kit.