Understanding Football Play Calling: Systems and Terminology

Question
I was wondering how plays are named in High School/College/NFL? I know that, in youth football, you can call a basic play (I-Right 26 Counter) but how are plays named in the higher levels of play? Is this all made up by the coach?

Answer
Dan,

Pretty much each team has a special system to call plays. They are obviously much more detailed as at the higher levels the play calls are long with formation shifts, motion, complex patterns, ect. Thats why qb's wear helmet radios and have play wristbands.

Mark