Albus Dumbledore, Was Headmaster of Hogwarts for most of harry's year's there.
Albus Dumbledore was Harry's Friend all the way through until Snape
Killed him with Avada Kedavra
But Snape Didn't Kill him for the fun of it, He Killed him for a reason.
Dumbledore Was the original founder of the Order Of the Phoenix, But was Put in
stress by Dolores Umbridge.
Harry Couldn't Be touched by Voldemort Under dumbledore's Protection.
Albus Dumbledore: Harry, Do You Know why Quirrell Couldn't Bear to have you touch him?,
It was because of your mother, She sacrifised Herself for you.