Robin Williams was found dead in his Tiburon, Calif. home on Monday, Aug. 11. He was 63.

As news of the tragic loss spread, famous fans of the actor and comedian, best known for his roles in "Mork and Mindy," "Aladdin," "Mrs. Doubtfire" and "Good Will Hunting," took to Twitter to mourn. Celebrities and fans alike remembered Williams as an actor, artist and friend. Check out some of the most heartbreaking and touching tributes on Twitter to the Hollywood legend.

I can’t believe the news about Robin Williams. He gave so much to so many people. I’m heartbroken.

— Ellen DeGeneres (@TheEllenShow) August 11, 2014

pic.twitter.com/UEtjQ1f2zS — Zelda Williams (@zeldawilliams) August 12, 2014

I could not be more stunned by the loss of Robin Williams, mensch, great talent, acting partner, genuine soul. — Steve Martin (@SteveMartinToGo) August 11, 2014

"Robin Williams was an airman, a doctor, a genie, a nanny ... and everything in between. But he was one of a kind." —President Obama — Barack Obama (@BarackObama) August 12, 2014

I know he and his buddy Jonathan Winters are making the angels laugh out loud — Meredith Vieira (@meredithvieira) August 12, 2014

A tweet cannot begin to describe the hugeness of Robin Williams heart and soul and talent. This is so sad. #RobinWilliams — Ben Stiller (@RedHourBen) August 12, 2014

I am deeply saddened. He was a lovely man who would keep everyone laughing even if he wasn't feeling good himself. RIP Robin Williams. — Ricky Gervais (@rickygervais) August 12, 2014

Very sad, very upset, very glad I did not have to hear about this though Twitter. Probably going to be taking some time off it for a while. — Mara Wilson (@MaraWritesStuff) August 11, 2014

pic.twitter.com/4Pyx4Kfuxe — Sarah Michelle (@RealSMG) August 12, 2014

Heartbreaking news about the late Robin Williams. May his soul now be at peace! — Rihanna (@rihanna) August 12, 2014

I am stunned and just reeling from the news of Robin Williams' death. He brought so much joy and heart to millions... Just, wow. — Neil Patrick Harris (@ActuallyNPH) August 12, 2014

RIP to one of the greatest comedic and dramatic actors of our time. We will miss you. #NaNuNaNu — Jenny McCarthy (@JennyMcCarthy) August 11, 2014

Mr. Williams visited me the first day of filming The Parent Trap. I will never forget his kindness. What an enormous loss. My condolences. — Lindsay Lohan (@lindsaylohan) August 11, 2014

My thoughts & prayers are with Robin Williams family & friends. He inspired so much of who I am and what I do. I will miss him greatly. — Zachary Levi (@ZacharyLevi) August 11, 2014

Robin Williams has died and I am very sad. From every comedian here at the Edinburgh Fringe Festival, we salute him & we say goodbye — Eddie Izzard (@eddieizzard) August 11, 2014

Condolences to the whole world. @robinwilliams RIP. #RobinWilliams — Drew Carey (@DrewFromTV) August 11, 2014

O Captain! My Captain! Rise up and hear the bells. Rise up, for you the flag is flung, for you the bugle trills. — Anna Kendrick (@AnnaKendrick47) August 11, 2014

He gave so many of us so much joy. I hope he knew that deeply. — P!nk (@Pink) August 11, 2014

To the kindest hearted man. Robin, know you will always be remembered by smiles, laughter and love. Thank you. Thank you. Thank you. — John Krasinski (@johnkrasinski) August 12, 2014

The first thing I ever wanted to be when I grew up was Robin Williams’ inhabiting of Popeye. #RIPRobinWilliams — John Mayer (@JohnMayer) August 12, 2014

I am named after a character from a Robin Williams TV show when my parents still lived in Africa. He meant so much, to so many, so far away. — Mindy Kaling (@mindykaling) August 12, 2014

Robin Williams was an early supporter of our Stand Up For Heroes event-A hero & a voice for wounded service members. pic.twitter.com/wScSDbfftX — Bob Woodruff (@BobWoodruff) August 12, 2014

Absolutely stunned and heartbroken. I dont know what to say. He was a huge part of my childhood. #RIPRobinWillams — Evan Rachel Wood (@evanrachelwood) August 11, 2014

Robin Williams changed my life. He was a great actor and a generous person. Through a scholarship, he made it possib… https://t.co/otEuiWrhPW — Jessica Chastain (@jes_chastain) August 12, 2014

Absolutely stunned to hear the news about Robin Williams. It's unimaginable to me that we've lost such a genuinely funny and sweet man. — Conan O'Brien (@ConanOBrien) August 12, 2014

Robin was as sweet a man as he was funny. If you're sad, please tell someone. — Jimmy Kimmel (@jimmykimmel) August 11, 2014

Genie, you're free. pic.twitter.com/WjA9QuuldD — The Academy (@TheAcademy) August 12, 2014