Welcome to my UML 2.0 Timing Diagrams tutorial. If you missed part one, you may want to check it out before proceeding here UML 2.0 Tutorial.
UML timing diagrams are used to detail interactions based on time. With timing diagrams you’ll describe when an event occurs, how long it takes for other participants to react and how long they’ll take to complete an interaction.
I cover pretty much everything about timing diagrams in the video that follows and the timing diagram cheat sheet that follows that should get you the rest of the way.