Who is Hodor from A Clash of Kings and what is their importance?

Hodor is the man who carries around Bran Stark, since Bran's legs don't work. Hodor is at Winterfell with Bran. He can only say his name and usually yells it in panic if something disturbing happens. He goes north with Bran Stark and Jojen and Meera Reed after Winterfell is burned by Ramsay Snow's men.