[luau] UML (unified modeling lang., not user mode linux)

[Charles Lockhart]

Anybody here know of a good tutorial or source of info on using UML? 
We've started using it here for our software projects, but I'm just not 
getting it.  I'm trying to put together a class diagram for a system we 
already have, but keep getting lost in what all the UML lingo means.

I've got a class called Ipengine.  I have two subclasses of Ipengine, 
ClockerIpengine and PixelIpengine.  All three contain instances of the 
class Command and the class CommandResponse.  Does that imply an 
agregation style relationship between the Command* classes and the 
*Ipengine classes?  Where do you find stuff like this out?

-Charles