Got their big breaks on Laugh In. Many had bits and pieces on TV, movies, and stage prior to that. I recall Arte Johnson on an old Jack Benny show. Johnny Brown was already a staple in stand up. Goldie Hawn had just made a movie and Tiny Tim had been at the bottom of the show biz rung. Judy Carne had just come off a short lived series with Peter Duell called Live On A Rooftop. None were major stars, but that changed. It's amazing the careers they forged. So many have passed as well.
There's a story Flip told on how he got his big break on the Tonight Show by convincing one of the scouts he was Gereldine. That lead to Laugh-In, which lead to his own show. He said something interesting in a TV guide interview when Flip was a top show: "Comedy is a serious business". I took it to heart and watched other comics preshow when still doing open Mike nights. They are very serious before the show, many will not take any drugs or drink even coffee prior to a perfoance. Me? I would have one beer before performing, then switch to coffee. Part of my act included taking a coffee break. I know now I should have included a newspaper because Will Rogers always got good laughs with that.