Beyond imbuing every deck of cards with a jesterly sense of fun, jokers have no real role in many games. Sure, you can use one to stand in for a missing card—but if that’s their main purpose, why have a design on them at all?

As HowStuffWorks explains, that wasn’t originally their main purpose. Jokers were added to the deck around the 1860s—long after card decks became common—to capitalize on the popularity of a game called euchre, from the Alsatian game juckerspiel. In it, the top two trump cards are the jacks, known as the “right bower” and the “left bower,” since bauer is the German word used for jack (its direct translation is farmer). But juckerspiel players created a card that could trump even the jacks. This card, called the “best bower,” is the joker.

Because joker sounds pretty similar to jucker and euchre, some people believe that’s where the name came from. But not everyone agrees with this. Playing card manufacturer Bicycle, according to its website, is “positive it’s no more than a coincidence.” It’s also possible that a jester character was chosen simply because it fit in with kings, queens, and the whole medieval court theme. The reason every deck includes two jokers when there’s only one best bower in euchre is also unclear; perhaps card makers just rolled with the convention of having an even number of cards to a deck.

Though euchre was eventually overtaken by bridge as the go-to card game in the U.S., jokers did get introduced in a number of other card contests, like poker, canasta, and war. In most instances, the joker serves as a wild card or a trump card.

[h/t HowStuffWorks]

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