Zacharius Knight "Zach" Galifianakis (born October 1, 1969) is an American comedian and actor, known for numerous film and television appearances including his own Comedy Central Presents special.

Galifianakis (pronounced ; Greek: Ζαχαρίας Γαλυφιανάκης) was born in Wilkesboro, North Carolina. His mother, Mary Frances, ran a community center for the arts, and his father, Harry Galifianakis, was an oil heating vendor who immigrated from Greece at the age of three. Galifianakis was raised in his father's Greek Orthodox faith, but now says he "isn't sure" on the subject of religion.

Galifianakis's cousin Nicholas Galifianakis is a newspaper cartoonist, and his uncle Nick Galifianakis is a former Democratic U.S. Congressman who lost a race for an open Senate seat in 1972 against Jesse Helms, launching Helms's career in the Senate.