Hugh Hefner, the iconic founder of Playboy, died Wednesday at the age of 91 of natural causes. 

In addition to his Playboy legacy, Hefner also co-produced hundreds of Playboy-branded videos and a few feature films, including Roman Polanski’s Macbeth and the Monty Python film And Now for Something Completely Different. He more recently appeared on television shows such as Curb Your Enthusiasm, Entourage and Sex and the City as well as in animated shows like The Simpsons and Family Guy.

Following word of his death, Hefner's family, friends, Playmates past and present as well as Hollywood figures took to social media to share their condolences.

Hefner's son, Cooper, who is also chief creative officer of Playboy, said in a statement, "My father lived an exceptional and impactful life as a media and cultural pioneer and a leading voice behind some of the most significant social and cultural movements of our time in advocating free speech, civil rights and sexual freedom."

Playmate and actress Jenny McCarthy tweeted, "Thank you for being a revolutionary and changing so many people's lives, especially mine. I hope I made you proud."

Actor Rob Lowe also tweeted that he had had a number of great conversations with Hefner over the years. "Was such an interesting man. True legend. What an end of an era," he said.

Read more statements and reactions below.