My parakeet used peck at my fingers or on the side of my cheek as he would kind of chirp/sing. He never bit me though, except that one time when he flew on my head when I was sleep. When I got Buzz a friend, Candy, I realized that when he used to tap his beak against my finger it was the same way he reacted to Candy. I think it's just another way to socialize. He would have so much fun, his head would bob too.