I started out in junior high playing AH,  SPI,  and Metagaming games.  One day while looking at the games on the shelf of my local hobby store,  I picked up a game with a picture of a wizard and a fighter in combat with a dragon.  This was the Holmes boxed set.  I could not make heads or tales of the rules.  My brother made a stab at the rules and we wound up playing a game which bore no resemblance as to how D&D was actually supposed to be played.  Bit by bit we figured things out until what we were actually playing was D&D.
Howndawg