The Joker is a playing card found in most modern French-suited card decks, as an addition to the standard four suits (clubs, diamonds, hearts, and spades). From the second half of the twentieth century, they have also been found in Spanish and Italian suited decks excluding stripped decks. The Joker originated in the United States during the Civil War and was created as a trump card for the game of Euchre. It has since been adopted into many other card games, where it often acts as a wild card, but may have other functions such as the top trump, a skip card (forcing another player to miss a turn), the lowest-ranking card or the highest-value card. By contrast, a wild card is any card that may be used to represent another card or cards; it need not be a joker. The Joker is unique within the French pack in that it lacks an industry-wide standard appearance.
In the game of Euchre, the highest trump card is the Jack of the trump suit, called the right bower (from the German Bauer or Jack); the second-highest trump, the left bower, is the Jack of the suit of the same color as trumps. The concept appears to have originated from Germany where the games, Juckerspiel and Bester Bube ("Best Bower") also used Jacks as best, right and left bowers. Around 1860, American Euchre players may have devised a higher trump, the "Best Bower", out of a blank card.
Samuel Hart is credited with printing the first illustrated "Best Bower" card in 1863 with his "Imperial Bower". Best Bower-type jokers continued to be produced well into the 20th-century. Cards labelled "Joker" began appearing around the late 1860s with some depicting clowns and jesters. It is believed that the term "Joker" comes from Jucker or Juckerspiel, the original German spelling of Euchre. One British manufacturer, Charles Goodall, was manufacturing packs with Jokers for the American market in 1871. The first joker for the domestic British market was sold in 1874. Italians call jokers "Jolly" as many early cards were labelled "Jolly Joker".
The next game to use a joker was poker around 1875 where it functioned as a wild card. Packs with two jokers started to become the norm during the late 1940s for the game of Canasta. Since the 1950s, German and Austrian packs have included three jokers to play German Rummy; in Poland the third joker is known as the blue joker; and, in Schleswig-Holstein, Zwickern packs come with six jokers.
Jokers do not have any standardized appearance across the card manufacturing industry. Each company produces their own depictions of the card. The publishers of playing cards trademark their jokers, which have unique artwork that often reflect contemporary culture. Out of convention, jokers tend to be illustrated as jesters. There are usually two Jokers per deck, often noticeably different. For instance, the United States Playing Card Company (USPCC) prints their company's guarantee claim on only one. More common traits are the appearance of colored and black/non-colored Jokers. At times, the Jokers will each be colored to match the colors used for suits; there will be a red Joker, and a black Joker. In games where the jokers may need to be compared, the red, full-color, or larger-graphic Joker usually outranks the black, monochrome, or smaller-graphic one. If the joker colors are similar, the joker without a guarantee will outrank the guaranteed one. With the red and black jokers, the red one can alternately be counted as a heart/diamond and the black is used to substitute clubs/spades. The Unicode for playing cards provide symbols for three jokers: red, black, and white.
Many decks do not provide the Joker with a corner index symbol, of those that do, the most common is a solid five-pointed star or a star within a circle. It is also very common for decks to simply use a stylized "J" or the word "JOKER" in the corner.
Joker collecting has been popular for an unknown amount of time but with the advent of the internet and social media, it has emerged as a hobby. Many unusual jokers are available for purchase online while other collectible jokers are catalogued online for viewing. The Guinness World Records has recognized Denoto de Santis, an Italian magician, as having the world's largest collection of jokers.
The Joker is often compared to "(the) Fool" in the Tarot or Tarock decks. They share many similarities both in appearance and play function. In Central Europe, the Fool, or Sküs, is the highest trump; elsewhere as an "excuse" (L'Excuse) that can be played at any time to avoid following suit but cannot win.
Practitioners of cartomancy often include a Joker in the standard 52-card deck with a meaning similar to the Fool card of Tarot. Sometimes, the two Jokers are used. An approach is to identify the "black" Joker with a rank of zero with the Fool and the "red" Joker with "the Magician", also known as "the Juggler", which is a card with a rank of one that is somewhat similar in interpretation and is considered the first step in the "Fool's Journey".
In a standard deck, there are usually two Jokers. The Joker's use varies greatly. Many card games omit the card entirely; as a result, Jokers are often used as informal replacements for lost or damaged cards in a deck by simply noting the lost card's rank and suit on the joker. Other games, such as a 25-card variant of Euchre which uses the joker as the highest trump, make it one of the most important in the game. Often, the joker is a wild card, and thereby allowed to represent other existing cards. The term "joker's wild" originates from this practice.
The Joker can be an extremely beneficial, or an extremely harmful, card. In Euchre it is often used to represent the highest trump. In poker, it is wild. However, in the children's game named Old Maid, a solitary joker represents the Maid, a card that is to be avoided.