Cat biting

My cat (7yo male) is a biter, He is a very sweet cat but he just seems to enjoy biting, they arent mean bites and he dosent hiss or anything he just likes to grab on with his teeth and i dont really understand why. he does it when he wants food or attention but also when im petting him so i dont think its just an attention thing. Its not too much of an issue but it would be nice to know why he does it if anyone has any idea. (Hes also learned to pull my hair but thats just for attention, probably not the best habit but we are working on that one)