Williams first rose to fame from the stand-up comedy circuit in the 1970s, with a manic improvisational style all his own. He appeared on the sitcom "Happy Days" and then starred as a lovable alien on its popular spin-off, "Mork & Mindy," from 1978 to 1982.
Williams went on to prove his serious acting talents as well, with critically praised performances in films like "Dead Poets Society" and "Good Will Hunting," for which he snagged an Academy Award nomination for Best Supporting Actor.
His performing style was at its purest in his standup act, as he impersonated a Russian immigrant or parodied anyone from John Wayne to Keith Richards.
Syracuse University's Bob Thompson says he didn't see this one coming. "Maybe his greatest accomplishment and what is so poignant about this news, is Robin Williams seems to be this guy who escaped all the things that took so many others," says Thompson. "We know it because he told us on countless talk show that he was living a dangerous lifestyle, and it was nice to hear him talk about surviving it." Ironically, he says many of the things that made him stood out was because he was "lubricated" by dangerous substances.
Thompson says for anyone to get a real glimpse of Williams' talent, it's to listen to him as the voice of the genie in "Aladdin." "Even though that never shows his face, the mere hyperactivity and the density of content he managed in that performance, whenever I watch it, I think just how amazing it was," says Thompson.