William Daniels
Daniels in 1976
Born	William David Daniels (1927-03-31) March 31, 1927 (age 99) New York City, U.S.
Alma mater	Northwestern University
Occupation	Actor
Years active	1943–present
Spouse	Bonnie Bartlett ​ (m. 1951)​
Children	3
President of the Screen Actors Guild
In office March 5, 1999 – October 15, 2001
Preceded by	Richard Masur
Succeeded by	Melissa Gilbert
Military career
Branch	United States Army
Service years	1945–1945
Website	williamdanielstheactor.com

William David Daniels (born March 31, 1927) is an American actor, known for his television roles, notably as Mark Craig on the drama series St. Elsewhere, for which he won two Primetime Emmy Awards; the voice of KITT on the television series Knight Rider; and George Feeny on the sitcom Boy Meets World, which earned him four People's Choice Award nominations. He reprised his Knight Rider role in the sequel TV movie Knight Rider 2000 and his Boy Meets World role in the sequel series Girl Meets World. He also portrayed Carter Nash (the actual identity of the eponymous comedic superhero) in Captain Nice.

Daniels's film roles include Mr. Braddock (Benjamin Braddock's father) in The Graduate, Howard Maxwell-Manchester in Two for the Road, and John Adams in the musical film 1776. He was president of the Screen Actors Guild from 1999 to 2001 and led the union's efforts during the 2000 commercial actors strike.

Daniels is also noted for having portrayed in film or on television the three most prominent members of the Adams political family: John Adams, his cousin and fellow founding father, Samuel Adams, and John Adams's son John Quincy Adams.