They have made references to two names, Harold and Hubert. Stanley Fafara says it was Harold, Miss Canfield calls him Harold in one of the early episodes, yet he said on the show it was Hubert.

Which one is it?

The correct name is Hubert.

Harold Hubert Horatio Whitney. (Actually, that's not it, but I think it sounds pretty cool.)

Wonder how he got the name Whitey.? I guess because of the blond hair.