Today, The Tonight Show primarily attracts guests who are already big stars, but back in the old days when it was hosted by Johnny Carson it was common for budding stars and unknowns to make their television debut on the show. The key to a successful run on The Tonight Show back then was one rule: make Johnny laugh. If you made Johnny Carson laugh, and if he invited you over to the couch, you were pretty much guaranteed to become the next big star.

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It had many names, the "Call To The Couch," "The Carson Springboard," etc. Whatever you call it, many stars admitted that they owe their fame and fortune to the magic touch of Johnny Carson. Here are just a few of them, and funny enough many went on to host their own talk shows too.

14 Andy Kaufman

Kaufman died in the 1980s, yet he remains one of the most legendary comedians because of his outlandish bits and his public pranks. After Kaufman showed off his bizarre bits to the world and was given Johnny's blessing, he landed a role in the iconic sitcom Taxi, where he co-starred with two other legendary stars, Danny DeVito and Christopher Lloyd.

13 George Carlin

Carlin was already a modestly successful comic when he did his first set on The Tonight Show but it was his first performance there when he showed the world he had made the leap from being a run-of-the-mill nightclub comic to a counter culture icon. He would then afterward guest host for Carson a few times and eventually got to be the first host of another NBC institution, Saturday Night Live.

12 Louie Anderson

Anderson had his network television debut on The Tonight Show in 1981. After impressing Carson, Anderson began to enjoy a wildly successful stand-up career that eventually led him to become a host himself. Anderson was the original host of the reboot of the game show Family Feud, a role now filled by Steve Harvey.

11 Jim Carrey

People often credit Carrey's time on the sketch show In Living Color as the official launch of his career but they forget that he got that job because of his success as a standup comedian. His talent was first noticed on television thanks to Johnny Carson's show.

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10 Bill Maher

The controversial political comedian was not always super political in his routines, although he always had some kind of biting social commentary. Carson was traditionally politically neutral on his show, but the now overtly political Maher impressed the host and received the coveted "Call To The Couch."

9 Eddie Murphy

Murphy was indeed a budding star on SNL at the time, but few fans who watched him on SNL knew he was also a great standup comic. All of that changed thanks to Carson and soon after Murphy got his now-legendary standup special Raw, where he wore his iconic red leather suit.

8 Ellen DeGeneres

DeGeneres impressed Carson with her self-defacing and seemingly shy and awkward humor, and that humor then led DeGeneres to get her sitcom, where she caused a huge stir when she used the show to come out of the closet. DeGeneres was one of the first people to play an outwardly gay character on primetime television. Although the sitcom was eventually canceled, DeGeneres soon moved on to her talk show, where she remained for nearly 20 years.

7 David Letterman

Before he was David Letterman the late night host, he was David Letterman the standup comedian. It was not long after he impressed Carson that Letterman got his first hosting job as the original host of Late Night, the show immediately following Carson that was later filled in by Conan O'Brien.

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6 Burt Reynolds

When Carson retired in 1991 Reynolds was one of the first to thank Carson for his career, according to the Los Angeles Times. After appearing on The Tonight Show to promote one of his earliest films, offers came rolling in for the star, and he soon became a sex symbol of his era.

5 Joan Rivers

Rivers not only impressed Carson so much that he invited her to his couch, but he also invited her to guest host and was probably the most frequent fill-in for Carson when he was either sick or unavailable.