Robin helped launch the careers of both Ben and Matt Damon by signing on to co-star in their 1997 film Good Will Hunting, which the childhood friends wrote the screenplay for. Robin won a best supporting actor Oscar for his portrayal of psychotherapist Sean Maguire.
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Good Will Hunting co-stars Matt Damon, Robin Williams and Ben Affleck
"Heartbroken. Thanks chief – for your friendship and for what you gave the world," Ben, 41, wrote on Facebook on Tuesday. "Robin had a ton of love in him. He personally did so much for people.
"He made Matt and my dreams come true.
"What do you owe they guy who does that? Everything," he added. "May you find peace my friend. #Robin Williams."
Ben Affleck's touching tribute to Robin Williams: 'He made Matt and my dreams come true'
Matt, 43, also paid tribute to the late comedic star, who took his own life on Monday.
"Robin brought so much joy into my life and I will carry that joy with my forever," he said in a statement. "He was such a beautiful man. I was lucky to know him and I will never, ever forget him."
Minnie Driver, who also appeared in the hit film, was left devastated by the news.
Hollywood has been left shocked and saddened by the death of Robin Williams
"My heart's broken," she wrote on Twitter. "Robin was a beautiful kind soul. Can't bear that he's gone. So incredibly sorry for his family."
The whole of Hollywood was left shocked and saddened by Robin's death, and tributes continue to flood in for the late actor.
His three children have since issued touching statements following their father's passing.
Robin Williams with his daughter Zelda
Robin's eldest son Zak, 31, said he had "lost my father and a best friend and the world got a little greyer", while his youngest child, Cody, 23, said he would "miss him and take him everywhere I go for the rest of my life, and will look forward, forever, to the moment when I get to see him again".
Robin's daughter Zelda, 25, added her own heartfelt words. "Dad was, is and always will be one of the kindest, most generous, gentlest souls I've ever known, and while there are few things I know for certain right now, one of them is that not just my world, but the entire world is forever a little darker, less colourful and less full of laughter in his absence."