​From Wikipedia, the free encyclopedia.   William Michael "Billy" Zabka (born October 20, 1965) is an American actor, martial artist, screenwriter, and film producer. Zabka is best known for playing bully types in several popular '80s films, such as his role of Johnny Lawrence in 1984's The Karate Kid. Description above from the Wikipedia article William Zabka, licensed under CC-BY-SA, full list of contributors on Wikipedia.