Retrospective: Robin Williams (1951-2014)

Sarah Michelle Gellar (left) and Robin Williams star in the CBS series 'The Crazy Ones.'

Actors Sarah Michelle Gellar and Robin Williams speak onstage during "The Crazy Ones" panel discussion at the CBS, Showtime and The CW portion of the 2013 Summer Television Critics Association tour at the Beverly Hilton Hotel on July 29, 2013 in Beverly Hills, California.

Robin Williams as Dwight Eisenhower, left, and Forest Whitaker as Cecil Gaines in a scene from "Lee Daniels' The Butler."

Robin Williams performs during the 6th Annual Stand Up For Heroes at the Beacon Theatre on November 8, 2012 in New York City.

Comedian Robin Williams accepts an award onstage at The Comedy Awards 2012 at Hammerstein Ballroom on April 28, 2012 in New York City.

Susan Schneider and husband Robin Williams attend The Comedy Awards 2012 at Hammerstein Ballroom on April 28, 2012 in New York City.

Robin Williams arrives at the Happy Feet 2 Australian Premiere at Hoyts Cinema on December 4, 2011 in Sydney, Australia.

Actor Robin Williams attends the Premiere of Warner Bros. Pictures' "Happy Feet Two" at Grauman's Chinese Theatre on November 13, 2011 in Hollywood, California.

Actress Zelda Williams (L) and actor Robin Williams attend the Premiere of Warner Bros. Pictures' "Happy Feet Two" at Grauman's Chinese Theatre on November 13, 2011 in Hollywood, California.

Cast members Robin Williams and Arian Moayed take a curtain call during the opening night of "Bengal Tiger At The Baghdad Zoo" at the Richard Rodgers Theatre on March 31, 2011 in New York City.

NEW YORK, NY - APRIL 05: Actors Robin Williams, Russell Brand, and Billy Crystal attend the after party for the New York premiere of "Arthur" at The Harvard Club on April 5, 2011 in New York City.

Actors Robin Williams and Harrison Ford backstage during the 38th AFI Life Achievement Award honoring Mike Nichols held at Sony Pictures Studios on June 10, 2010 in Culver City, California.

Robin Williams (left) and John Travolta in "Old Dogs."

Actor Robin Williams and American Idol host Ryan Seacrest onstage during the taping of Idol Gives Back held at the Kodak Theatre on April 6, 2008 in Hollywood, California.

Actor Tony Shalhoub and actor Robin Williams attend the Campaign for a New GI Bill hosted by the Student Veterans of America at the Beverliy Hilton hotel on June 22, 2008 in Los Angeles, California.

Actress Halle Berry (L) presents the Favorite Funny Male Star to actor Robin Williams onstage during the 33rd Annual People's Choice Awards held at the Shrine Auditorium on January 9, 2007 in Los Angeles, California.

Freddie Highmore and Robin Williams in the music-driven drama "August Rush."

Host Jack Black (L) slimes actor Robin Williams onstage at the 19th Annual Kid's Choice Awards held at UCLA's Pauley Pavilion on April 1, 2006 in Westwood, California.

Google co-founder Larry Page (L) jokes with actor/comedian Robin Williams during Page's keynote address at the International Consumer Electronics Show January 6, 2006 in Las Vegas, Nevada.

Robin Williams (right) and Ben Stiller in "Night at the Museum" (2006).

Actor Robin Williams poses with his wife Marsha and daughter actress Zelda Williams at the "House Of D" film premiere at Loews Lincoln Square Theater April 10, 2005 in New York City.

Robin Williams (2nd R, top) poses for a picture with US soldiers upon his arrival at a military base near Baghdad's international airport 14 December 2004.

Robin Williams voiced 'Lovelace' in the 2006 film "Happy Feet."

Billy Crystal, left to right, Muhamad Ali, Robin Williams, and Reba McEntire pose for photos in the VIP room Saturday evening before the Fight Night Charity Event at the Arizona Biltmore Resort in Phoenix in 2003.

Robin Williams in "One Hour Photo."

Robin Williams and Al Pacino in "Insomnia" (2002).

402917 07: Actors Robin Williams (L), Danny Woodburn (C) and Harvey Fierstein attend the premiere of the film "Death to Smoochy" March 26, 2002 in New York City.

HOLLYWOOD, : US actor Robin Williams(R) arrives with his wife Marsha(L), daughter Zelda(front L) and son Cody(front R) for the premiere of his new film "Bicentennial Man" 13 December in Hollywood.

Actor Robin Williams displays his Oscar trophy after being named Best Supporting Actor for his role in the movie, ''Good Will Hunting,'' at the 70th Academy Awards in Los Angeles, California in 1998.

Academy Award-winning actor Robin Williams wears a clown nose as he places his hands in cement during his hand and footprint ceremony outside Mann's Chinese Theatre 22 December in Hollywood, California. Williams is currently starring in the critically acclaimed film "Patch Adams" about a doctor who uses humor to help heal his patients.

Robin Williams stars as Hunter Patch Adams, a misfit medical student in "Patch Adams."

Actors-writers Matt Damon (L) and Ben Affleck (R) pose with actor Robin Williams with their Oscars they won for "Good Will Hunting" at the 70th Annual Academy Awards 23 March in Los Angeles.

Robin Williams, left, and Matt Damon appear in a scene from the movie "Good Will Hunting."

Robin Williams in the Walt Disney picture "Flubber."

Armand (ROBIN WILLIAMS, right) and Albert (NATHAN LANE) share a long-term committed relationship in "The Birdcage."

Robin Williams wrestles with an alligator in a scene from the movie "Jumanji."

Robin Williams in "Mrs. Doubtfire" (1993).

Genie (voiced by Robin Williams), Aladdin (voiced by Scott Weinger) and Abu (voiced by Frank Welker) in the 1992 Disney film "Alladin."