HELP! Newbie to OOP. How do objects communicate?

I’m sorry if this sounds like a dumb question, but I’m new to Object-Oriented Programming. I have 2 different custom objects I’ve created for a tutorial app (a steplist object which holds steps which a student must perform in a module, and a studentData object holding data on when a user gets an error). These 2 objects have nothing really in common with each other so I really can’t use inheritance with them.

So the issue is: How can I get the steplist object to tell the studentData object when there is an error? Again, I’m very new to OOP, especially within Flash, so if someone could please explain how to do this for me.

Chris