Texas Hold'em or just Holdem is a community card game played between 2 and 9 players. The most common number of players are 2 (heads-up), 6 (6-max) and 9 (full ring). The objective of the game is to make the best 5 card hand from any combination of 2 private hole cards and 5 community cards which are shared among all players.
Holdem uses a dealer button to indicate which player is the dealer for that hand. The dealer button rotates around the table in a clockwise direction shifting one position at the end of each hand. Holdem is always played with blinds, and optionally with antes also. The player immediately to the left of the dealer posts the small blind and the player to their left posts the big blind. If antes are used, then every player must post the ante at the beginning of the hand before any cards are dealt. In a heads up situation, the dealer posts the small blind and the other player posts the big blind.
Each player is initially dealt 2 hole cards face down. Then there is a round of betting. The betting round begins with the player immediately to the left of the big blind and continues around the table in a clockwise direction. After this betting round has completed, assuming the hand hasn't finished, 3 community cards are dealt face up in the center of the table. This is known as the 'flop'. These are the first 3 of a total of 5 community cards that are shared between all players in the hand. At this point, there is another round of betting beginning with the player immediately to the left of the dealer.
The 4th community card, known as the 'turn', is then dealt face up and another round of betting follows. After this, the 5th and last community card, known as the 'river' is dealt, and there is now a final round of betting. When this round of betting has completed, players remaining in the hand must now show their hole cards in order to make a claim on the pot. The first person to show their hand must be the last aggressor (ie the person called). Other players in turn will then show their hands in clockwise order. It is not necessary to show your hand if it cannot beat the best hand already shown. If there was no action on the final betting round, then the first player to show is the player to the left of the dealer. Players with hands of equal value will split the pot.
Side pots occur when 1 or more players are all in, but there are other players still remaining in the hand with chips. In this case, further action between the other players will result in separate pots being created that only they can claim. Any person who is all in will get to see all community cards and will be able to make a claim for the main pot, but will not share in any side pots that have been created.
Holdem can be played with a no limit, pot limit, or fixed limit betting structure. See the section on Betting Limits for more information.