What is playing cards joker?

Playing cards joker is a card found in standard decks of playing cards, used mainly in trick-taking and trump card games. The Joker is usually a wild card, meaning it can be played as any card required to complete a poker hand. There are typically two Jokers in a standard deck, one with a red background and one with a black background, and can be differentiated by the different colored backgrounds and the letter "Joker" printed on the card. When playing games that include the Joker, players may agree on additional rules to govern how the Joker can be used. The origins of the Joker are unclear, but it is believed to have been created in the United States during the Civil War period and has since become an iconic symbol in popular culture.