Official poker consists of a game in which each player receives five cards, bets into a pot, and shows their hand. In most games, the highest-ranking hand wins. Some variations use a different card-ranking system. Some allow players to protect their hands by covering them with their chips or a different object. Other rules are negotiated on a case-by-case basis, depending on the specific game.
Most poker games are played with a fixed number of rounds, with the highest-ranking hand winning. However, a few variants are played with a variable number of hands. These games are sometimes known as a mixed game, or a progressive game.
The earliest American game recorded is draw poker, first described about 1850. As Allen Dowling points out, it is a direct descendant of the earlier English game brag. It was a game that reached America in the late colonial period via English emigrants and British colonials, or perhaps Americans returning from transatlantic visits. It may also have influenced the development of stud poker and other community card games.
The earliest form of poker in America was probably a five-card draw. It is the version that is most commonly seen in movies and on TV, and it is still popular at casual kitchen table games. It is also the game used in many tournaments. However, it began to fade in popularity during the second half of the 20th century as Texas hold ’em and other community-card games emerged.