Fifty years ago, there was only one undisputed king of late night television.

These days, late-night TV is probably more varied than it's ever been. There's an endless variety of viewing choices for the insomniac … but there was a time when that wasn't the case. Fifty years ago, there was one undisputed king of late night, and that king was Johnny Carson (1925 - 2005).

From his "Tonight Show" debut in 1962 all the way to his emotional retirement in 1992, Carson gave us a reason to keep the TV on after the late night news. Today, we're looking back at those 30 years with a clip from each decade Carson hosted "The Tonight Show."

See Photos of Johnny Carson and His Tonight Show Guests

1960s. "The Tonight Show" (then called simply "Tonight") existed before Carson took the reins, of course — Steve Allen was its first host, before Jack Paar ran the show. When Paar left (not long after his famous walkoff, which probably destroyed any chance he had to achieve the longevity Carson would see), several others were approached for the position — Jackie Gleason, Bob Newhart, Groucho Marx, Joey Bishop — but they all declined, leaving the stage open for Carson to begin his reign over late night.

1970s. In 1972, the show moved from New York to Burbank, California, giving Carson a great new line: "beautiful downtown Burbank." Other than that, it was business as usual, with Carson's trademark humor shining through in interviews and monologues. He wasn't above letting low-key bandleader Tommy Newsom take the spotlight from time to time, too.

1980s. In 1980, "The Tonight Show" went from a 90-minute show to a 60-minute one, and Carson began bringing in guest hosts on Monday nights. Joan Rivers was a longtime "permanent" guest host, as was Jay Leno. In 1987, the show's 25th year, Carson won a Peabody Award for his contributions "to television, to humor, and to America."

1990s. Carson was still much-loved when he retired from "The Tonight Show." We suspect there were a lot of fans with "just a little dust in their eyes" when he delivered his farewell on May 22, 1992:

"And so it has come to this... I, uh...am one of the lucky people in the world; I found something I always wanted to do, and I have enjoyed every single minute of it. I want to thank the gentlemen who've shared this stage with me for thirty years, Mr. Ed McMahon... Mr. Doc Severinsen... and you people watching. I can only tell you that it has been an honor and a privilege to come into your homes all these years and entertain you... And I hope when I find something that I want to do, and I think you would like, and come back, that you'll be as gracious in inviting me into your homes as you have been. I bid you a very heartfelt good night."