A invitation to my classmates and the great teacher Hi, Are you same old still? I am learning Unified Modeling Language(UML), it's the blueprints of a software system, A picture is worth a thousand words, so there are fourteen types of diagrams in UML. Activity Diagram is one of them. I drew one for inviting you to take a trip. What do you say? Louie Chen 2013/04/11 10:00 AM.