Some of the greatest television shows in history lasted only a few seasons (Arrested Development - 3 seasons). A few barely made it past a dozen episodes (Firefly - 14 episodes). Yet a long list of run-of-the-mill sitcoms somehow manage to stay on the air for years. Funny or Die looks at nine such shows that lasted far, far longer than you might have realized.
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If a friend asked you if you've ever heard of the show Wings, you'd likely respond with "Oh sure, short-lived NBC sitcom from the 90s. Probably on a few seasons." And when you'd be told it was actually on eight seasons, your friend would have to get a mop because your mind just exploded all over the floor.
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also i'm not surprised that king of the hill was on for so long because it was amazingly consistent and one of the best cartoons ever. (if not the best)
i have seen every episode of king of the hill and most of them more than once. it is brilliantly satirical, rife with original characters, and devoid of much of the outlandish and crass humor that other cartoons rely on.