Hagrid is half giant and he stands almost twice as tall as a normal man.  Hagrid commonly wears a huge moleskin overcoat with many pockets where he carries all manner of things.  He may be large, but he is kindly, tender and loving.  He likes all kinds of animals and is always trying to befriend fearsome monsters and treat them as pets.  In 1942 he made friends with Aragog, an Acromantula (spider).  In the spring of 1992 he tried to hatch and keep a baby Norwegian Ridgeback dragon, which he named Norbert.

Hagrid attended Hogwarts, starting in 1940. In 1943, when he was a student there, he was falsely accused by Tom Riddle of opening the Chamber of Secrets and releasing a monster. Hagrid was expelled. Albus Dumbledore, then the Transfigueration Teacher at Hogwarts, arranged for him to stay on as gamekeeper. 

In 1981, he gets baby Harry Potter from the ruins of his parent's house and brings him to Dumbledore at the Dursley's house on Privet Drive.

In July of 1991 he gets Harry from the Dursleys and goes with him to Gringotts and takes him to the Leaky Caldron and helps him buy his school things in Diagon Alley.

In May of 1993 he was sent to Azkaban when old suspicians were revived by a seies of problems at the school.  In June of 1993 after 50 years of suspicion and accusation his name was cleared through the efforts of Harry Potter and his friends.

In October of 1994 Hagrid met Olympe Maxime, a lady as large as Hagrid who refused to acknowledge her giant heritage,  when she brought her students from xxx  to compete at the tri wizard games.  Hagrid went to visit the Giants of the north in 1995.

Hagrid was not allowed to do magic before his name was cleared, although it seems that his broken wand was somehow imbedded in his pink umbrella and he did cast a spell or two. Now he is allowed to do magic, but as he was never properly trained, he'll always be somewhat inept at it.