Talented actor behind several voices on The Simpsons, including Moe Szyslak, Chief Wiggum, Comic Book Guy, Carl Carlson, and Apu Nahasapeemapetilon. He has also appeared in a number of films including Along Came Polly, Mystery Men, The Smurfs, America's Sweethearts, and Night at the Museum: Battle of the Smithsonian.
He imitated and memorized many scripts, shows, and skits as a child. He studied at Tufts University.
He had a recurring role as a scientist named David on the NBC sitcom Friends. He briefly appeared in the music video for "All Star" by Smash Mouth.