2 year olds are starting to feel independence and have lots of emotions- kinda scary when you don't have much language. When they feel angry they tend to go to their "animal" selves (so to speak)....they hit, push, kick, bite, scream, etc. Problem is, it works! People give you back their toys or give you what you want if you will bite them if they don't!!!! Time out and teaching better responses can help. After he hits, and AFTER he has a time out (try about 2 minutes of a "quite time" AFTER he has quit protesting.....) have him come back into the room and practice touching nicely- then praise him for his good behavior. Whenever you see him touching nicely/showing appropriate affection- praise him like crazy. He will cope a clue soon: good behavior = fun/bad behavior = time out. He's not dumb- just doesn't have the words to express himself quite yet (he's pretty PO'd about losing a toy- but can't swear yet!). All too soon you will wish for the simpler days of bite and scream rather than the "I hate you"s