Skipper's the leader of the penguins.
Kowalski is Skipper's right hand.
Rico, a smart and silent penguin who is only expressed through grunts and squeals, and he's also the only one who doesn't talk.
Private's an eager, lowly penguin.
Skipper: Hello, recruit! Welcome to Penguin HQ, located inside under our own habitat at the Central Park Zoo, in New York City. I'm Skipper, and these are my three comrades, Kowalski, Rico, and Private.
Kowalski: At your service.
Private: Hello!
Rico: Heheheh! Kaboom! KABOOM!
Netwrck 
