Poker is a card game in which players wager money on the outcome of a hand. It has many variants but all involve betting and a showdown to determine the winner. While luck plays a significant role in the game, the decisions made by players are often based on expected value and other factors such as psychology and strategy.
Each player places a bet in the pot before the cards are dealt. A player who bets more than the previous bettor is said to raise. A player who does not raise is said to call. Players may also bet by bluffing, in which case they pretend to have a superior hand when they know that other players will not call their bets.
Once the first round of betting is complete the dealer puts three cards face up on the table that anyone can use (this is called the flop). Everyone still in the hand then gets another chance to bet/raise/fold.
Once the third round of betting is complete the dealer puts a fourth card on the board that everyone can use (this is called the turn). Once again everyone gets another chance to bet/raise/fold. Finally, the fifth and final community card is revealed in the final betting round (called the river). If a player has the best five-card poker hand then they win the pot.