According to legend, the original idea for "Jeopardy!" (originally to be named "What's the Question?") grew out of a conversation between Merv Griffin and his wife about the quiz show scandals of the late 1950s. Instead of being sneaky about it like "Twenty-One" and "The $64,000 Question," "Jeopardy!" would readily admit to giving the contestants the answers. They just wouldn't give them the questions.

The Art Fleming version premiered on NBC on March 30, 1964, at 11:30 A.M. Eastern time, and moved to the noon time slot on September 27, 1965, where it became a big hit among people eating lunch.

On this version, the dollar values ranged from $10 to $50 in the first round and $20 to $100 in Double Jeopardy!. The answers were printed on cards that were manually revealed by stagehands behind the game board. Contestants could ring in as soon as the host started reading the answer, and especially on the lower-valued clues, it became more of a contest of reflexes than anything else. (Since the cards were being pulled manually, the amount of time it took to reveal them would vary.) All three contestants kept the money they had earned during the show, although if they ended up with a negative amount, they didn't have to reach into their wallets. The winner returned the next day.

Eventually, NBC decided to screw with the time slot, moving "Jeopardy!" to 10:30 A.M. in January 1974, and then to 1:30 P.M. in July 1974. It last aired on January 3, 1975, although a syndicated version was also being produced throughout the 1974-75 season.

"Jeopardy!" returned to NBC on October 2, 1978, at 10:30 A.M., with some major changes to the rules. At the end of the first round, the contestant in third place was eliminated, and then the contestant in second place was eliminated at the end of Double Jeopardy!. The winner would then play a bonus round called Super Jeopardy!, which used a third complete game board on which they would have to correctly question five answers in a row (across, down, or diagonally) before missing three. The prize was $5,000.

NBC moved it to the familiar noon slot in January 1979, but it was being clobbered in the ratings by "The Young and the Restless," so it last aired on March 2, 1979.

Because of the sudden interest in trivia in the early 1980s, not to mention a certain "Weird Al" Yankovic song, Merv Griffin felt the time was right to bring back "Jeopardy!," this time in syndication, where it premiered September 17, 1984, with Alex Trebek, answers displayed on computer monitors, the return of a 3-person Double Jeopardy! and the original Final Jeopardy!, dollar values that were ten times those of the original show, and a new "only the champion keeps the cash" policy. At first, contestants were allowed to ring in immediately as on the old show, but that was soon changed to requiring the contestants to wait until Alex was finished.

Many local stations put the new syndicated version in daytime time slots or in the late night hours, where it performed poorly, but a few stations that put it on at 7:00 or 7:30 P.M. had success with it, especially when it was paired up with the syndicated version of Merv Griffin's other show, "Wheel of Fortune," which had premiered in 1983. More and more stations began to schedule the "Wheel"/"Jeopardy!" tandem at 7:00, culminating in ABC's flagship station, WABC in New York, deciding to switch the network news from 7:00 to 6:30 and put "Jeopardy!" on against the CBS and NBC evening newscasts. "Jeopardy!" won handily, eventually prompting WCBS and WNBC to also put on entertainment programming at 7:00.

A special tournament of champions with a prize of $250,000 called "Super Jeopardy!" aired Saturday nights on ABC in the summer of 1990, but the ratings were low. There were two format changes: in the first rounds, four contestants competed in each game, and the answers on the board were given point values instead of dollar values (200 to 1,000 in the first round and 500 to 2,500 in Double Jeopardy!). Many of the games consisted almost entirely of contestants trying to pick Potent Potables for $1,500 or whatever, and Alex reminding them they were playing for points, not dollars.

As of November 26, 2001, to counter the big-money prime time quiz shows such as "Who Wants to Be a Millionaire," "Jeopardy!" doubled its dollar values, to $200 to $1,000 in the first round and $400 to $2,000 in Double Jeopardy!.

Two variants of "Jeopardy!" have run concurrently with the Alex Trebek version. "Jep!," hosted by Bob Bergen, a version with children as contestants, ran briefly in syndication in 1998. "Rock and Roll Jeopardy!," with host Jeff Probst, is a rock 'n' roll-themed version that has aired on the VH1 cable channel since 1998.

Reruns of the Alex Trebek version of "Jeopardy!" have been a mainstay on the Game Show Network schedule since it began transmitting, and "Rock and Roll Jeopardy!" and "Jep!" are also rerun. Most of the videotapes of the first Art Fleming version were destroyed, but GSN has shown the 2,000th episode special (in which Mel Brooks made a guest appearance as The 2,000-Year-Old Man), and there may be a few more in broadcast quality condition. The 1978-79 version probably still exists, but once you've seen the bizarre bonus round once, there's no good reason to see it again.