UML Distilled Martin Fowler

State Diagrams  State Transition Diagrams define a number of states and the transitions between the states

Harel Statechart

When to use State Diagrams  Describing an object across several user- cases

Activity Diagrams  The activity diagram describes the sequencing of activities, with support for both conditional and parallel behavior. An activity diagram is a variant of the state diagram where the states are activity states.

Activity Diagrams

When to use Activity Diagrams  Analyze a user-case  Understanding workflow  Describe a complicated sequential algorithm  Dealing with multi-threaded applications Do not use it when:  Trying to see how objects collaborate  Trying to see how many objects behave over their lifetimes

Deployment Diagrams  A Deployment Diagrams shows the physical layout of components on hardware nodes. A deployment diagram is a good place to show how components and objects are routed and move around a distributed system.

When to use Deployment Diagrams  Distributed Systems