Your cat has a special kind of greeting for you to show that you are his favorite person. He will come over and rub his head and body against your legs, or even "head-butt" you. This is a very personal cat ritual and involves the three primary scent glands - on his forehead, at the base of his tail and on his cheek. This way your cat will know that he has left his special scent on you. The scent is too delicate for you to smell but it is there. He will love it and purr away if you stroke him and talk to him while he is doing it.
Of course it could also be his way of reminding you that there is nothing in his food dish! One of my foster-cats, Magic, will head-butt me to let me know that he wants to come on my lap. He won't jump up but this is his way of getting me to pick him up and put him on my lap.