Stars including Mel Brooks, Dick Van Dyke, George Clooney and Russell Crowe have paid tribute to the late comedy great Carl Reiner, calling him "a gem".
Reiner died aged 98 of natural causes on Monday at his home in Beverly Hills, his assistant Judy Nagy confirmed.
He helped to create The Dick Van Dyke Show, and had a partnership with Brooks.
"Carl was a giant," tweeted Brooks, who first met Reiner in 1950 on Your Show of Shows.
"Unmatched in his contributions to entertainment, he created comedy gems," he went on.
He added of his "best friend" and comedy partner that "there was no better straight man in the world".
Reacting to the news, Van Dyke commented that Reiner was his "idol". He tweeted: "He had a deeper understanding of the human condition, than I think even he was aware of.
"Kind, gentle, compassionate, empathetic and wise. His scripts were never just funny, they always had something to say about us."
The prolific writer, comedian, director and actor also directed several films including Steve Martin vehicles The Jerk (1979) and All of Me (1984).
He was in 2001's Ocean's Eleven and its two sequels as conman Saul Bloom.
Clooney, who played Danny Ocean, told Variety: "Carl Reiner made every room he walked into funnier, smarter, kinder. It all seemed so effortless. What an incredible gift he gave us all."
Gladiator star Crowe also called Reiner "a gem", recalling hosting the annual Directors Guild of America Awards alongside the late actor on several occasions.
"By the third year I was totally comfortable in that environment and made a little remark from the stage about how much I enjoyed seeing and being with Carl and what an honour it was," Crowe wrote on Twitter.
"When I left the stage that third year, Carl turned to the audience and dead panned, 'I've never met that guy before in my life'."
Reiner also acted in films such as The Russians Are Coming, The Russians Are Coming (1966).
He was a close friend of fellow sketchwriter Brooks, and the pair found a new audience with their 2000 Year Old Man routines, which spawned books and an animated TV special.
Reiner's agent recently posted a picture of the pair supporting the Black Lives Matter movement along with Reiner's daughter.
MY HEROS CARL REINER ANNIE REINER & MEL BROOKS pic.twitter.com/yimJbwoqCU— George Shapiro (@georgeshapiro) June 28, 2020
In his 90s, virtually every day in Beverly Hills, Reiner met with Brooks, after they both lost their wives, and they would sit on Reiner's sofa watching movies, telling jokes and recalling a lifetime of comedy.
Reiner started acting in the US army during World War Two. In the 1950s, fellow writers on Your Show of Shows included Brooks and Neil Simon, creating a combination of silliness and satire.
He won several Emmys writing and producing the Dick Van Dyke Show, in which he played temperamental variety show host Alan Brady, the boss of Van Dyke's character, Rob Petrie.
Last night my dad passed away. As I write this my heart is hurting. He was my guiding light.— Rob Reiner (@robreiner) June 30, 2020
A reprisal of his Alan Brady role three decades later, for a guest turn on the 1990s sitcom Mad About You, earned Reiner another Emmy.
His directing credits included 1977 comedy film Oh God!, starring George Burns, and more Steve Martin films including Dead Men Don't Wear Plaid and The Man with Two Brains.
Reiner also starred on Broadway and wrote many books, including several for children.
He was still doing voice roles in his 90s and had a key role in a documentary about people who keep busy into their tenth decade, titled If You're Not in the Obit, Eat Breakfast.
Reiner once wrote in his book My Anecdotal Life: "Inviting people to laugh at you while you are laughing at yourself is a good thing to do. You may be the fool but you are the fool in charge."
Tributes have been paid by stars including William Shatner and Rosanna Arquette.
Condolences to the family of Carl Reiner. From the writers room of Sid Caesar to recreating those times for the Dick Van Dyke show, Carl was a master at his craft. I knew him only peripherally but it was a pleasure to have known him.😞— William Shatner (@WilliamShatner) June 30, 2020
He leaves three children, artist Annie, artist Lucas and actor and director Rob Reiner - behind the likes of This is Spinal Tap, The Princess Bride, Stand By Me, A Few Good Men and When Harry Met Sally.
Reiner's wife of 64 years, Estelle, died in 2008.