Today I received a new task that they wanted me to be familiar with the whole business logic chain, so I started to use UML usecase diagram to represent the relationship. Actually I used to draw class/sequence diagrams via Jude, at this time I investigated couples of UML tools that can easily work both on Mac and Windows, e.g. astah, ArgoUML, LucidChart, Visual Paradigm. Considering the free licence, I choosed StarUML that is free and also works well on MacBook Retina.

Thus, I took Learning UML 2.0 as a reference.

There are the most common top 4 useful diagrams, i.e. use case, class, sequence, activity diagram.

Let's get started with use case diagram example. To show your system's boundary on a use case diagram, draw a box around all of the use cases but keep the actors outside of the box.