William Maher, Jr., (born January 20, 1956) is an American stand-up comedian, television host, political commentator, actor and author. He hosted the late-night television talk show Politically Incorrect on Comedy Central and ABC, and is currently the host of Real Time with Bill Maher on HBO. On June 1, 2006, he also began hosting an Internet-exclusive talk show on Amazon.com entitled Amazon Fishbowl.

Maher is known for his political satire and sociopolitical commentary. His commentaries target a wide swath of topics, from the right-wing to the left-wing, bureaucracies of many kinds, political correctness, Hollywood, the mass media, and persons in positions of high political and social power, among many others.  Maher is number 38 on Comedy Central's 100 greatest stand-ups of all time.

Maher began his career as a stand-up comedian and actor, and he continues to act and tour occasionally. He was host of the New York City comedy club Catch a Rising Star in 1979. Thanks to Steve Allen, he began appearing on Johnny Carson's and David Letterman's shows in 1982. He made limited television appearances, including two separate appearances on Murder She Wrote -- notably, as Maher likes to point out, as two different characters. He has also appeared in several films, usually in a comic role. His feature film debut was in D.C. Cab (1983), and he has also appeared in Ratboy (1986), Cannibal Women in the Avocado Jungle of Death (1988), and Pizza Man (1991).