Not all examples on this list are positive. Because sometimes you make history in a bad way. It happens. And it happened in the most unfortunate of ways during the 5th season of Happy Days.
In its first few seasons, Happy Days was gleefully beholden to the nostalgia of the 50s, complete with simple, relatable stories about friendships and families. But as the show went on, the storylines became bigger, the comedic performances became broader, and The Fonz transformed from a bit character into the larger-than-life center of it all.
Fonzie had become almost superhuman in his coolness, which led to the writers piling on one outlandish idea after another. Enter, this pile of ridiculousness, wherein Arthur Fonzarelli -- wearing swim trunks and his signature leather jacket -- ski jumps over an actual shark.
Not only was the stunt pointless from a story standpoint, it actually went against many of the characterizations that had been built up by that point.
The show remained on the air for another six years, but it was never quite the same. Fonzie jumping the shark signified a major cultural shift in the television industry, and gave us a brilliant shorthand for the moment a show becomes too gimmicky for its own good.