Heroes?

I'm listening to Chris Rice's song, "Need a Hero".
This weekend, I talked to 2 girlfriends about making a list of my favorite people.
These two influences, conbined with some other stuff, has cause me to wonder:
What is a hero?
as defined by princeton.edu-
a man distinguished by exceptional courage and nobility and strength;
champion: someone who fights for a cause
(classical mythology) a being of great strength and courage celebrated for bold exploits; often the offspring of a mortal and a god
So, I guess I was thinking more of role models...
someone worthy of imitation;
Who are your heroes(role models) and why?
Do your heroes (role models)change?
Are your favorite people your heroes (role models)?
Why/Why not?

Tell me your thoughts!
I was talking to some of my personal role models this weekend, and thinking about my heroes over the past couple of years. my mom is one of my heroes. The people I love and respect are my role models. how about you?