Welcome to my tutorial on UML 2.0 Activity Diagrams! In this tutorial, I'll show you all of the symbols used to create activity diagrams.
Activity diagrams show what actions occur step-by-step to achieve a given goal. Activity symbols are very similar to flowchart notation, so you should find this topic very easy to learn.
I have the entire image I taught from on my site. I think it will be a great cheat sheet. The program I use is UMLet. It is free and works on all OSs.