UML: Introduction tutorial and Activity Diagrams [video]
After reading UML 2.0 Reference Guide and watching few video tutorials I have found one that is just amazing and helped me learn the basics of UML and components used at different types of diagrams faster. Derek Banas is author of these video tutorials and they are available at his Youtube channel and at http://www.newthinktank.com/
UML 2.0 Tutorial
UML 2.0 Activity Diagrams
P.S. If you would like to view all UML 2 tutorials from Derek Banas, please follow this link.