John Ratzenberger (born April 6 1947) is an American actor born in Bridgeport, Connecticut. He is perhaps best known for his role as "Clifford C. 'Cliff' Clavin, Jr." in the Cheers (1982) TV Series.

His acting credits include 47 productions and an additional 22 notable television appearances. His first role was a Patron in The Ritz (1976), and since then he has appeared in notable movies including Superman and Superman II as a NASA controller, Star Wars: Episode V - The Empire Strikes Back (1980) as "Major Derlin", Gandhi (1982) as an American Lieutenant, and all five of Pixar Animation's feature films (as "Hamm" in Toy Story (1995) and Toy Story 2 (1999), as "PT Flea" in A Bug's Life, as the Abominable Snowman in Monsters Inc, and as a school of moonfish in Finding Nemo).