Official poker, also known as card games of the game of cards, is a card-based gambling game that features betting for an amount of money or chips contributed by the players. Players compete for a sum of these chips (called the pot) based on the strength of their hand and their prediction of what their opponents may do. It is a card game that can be played socially for pennies or professionally for thousands of dollars.

In the early 19th century, poker evolved into a full-fledged card game with a specific set of rules. Some of the key rules include the betting round where each player has the option to call, raise, or fold. After the betting round, all players reveal their cards and a winner is determined by the highest-ranked hand according to the official poker hand rankings.

While it is possible to play a game of poker without any official rules, it is recommended that a written code of poker laws be adopted. This is important to ensure the consistency of poker rules between players, tournaments, and casinos. Moreover, a written code of poker laws can serve as a final arbiter to settle any disputes or disagreements that arise during a game of poker.

Although Brag — the English national vying game — is more ancient, it is not as well-known as Poker. The development of Poker is often credited to General Schenck, the American ambassador to Britain. In fact, he was reported to have taught the game on a weekend retreat at his Somerset country home in 1872.