In poker players bet into a communal pot during the course of a hand, and in which the player holding the best hand at the end of the betting wins the pot. During a given betting round, each remaining player in turn may take one of four actions:

check = betting zero, but not forfeiting your interest in the pot
bet or raise = betting more than preceding bets you are forcing successive players to match or exceed or else forfeit all interest in the pot
call = betting the same as preceding bets and thus maintaining your interest in the pot
fold = surrendering your interest in the pot in response to another player’s bet, accompanied by the loss of your cards and previous bets
Betting proceeds in a circle until each player has either called all bets or folded.

Poker is played with a standard 4-suit 52-card. The ace is the highest card, but can sometimes play low, as explained below. At the showdown, the remaining players compare their hands according to this ranking:

Straight flush, five cards of the same suit in sequence (i.e. 45678 of diamonds). The best straight flush is AKQJ10 known as the royal straight flush.
Four of a kind, four cards of the same rank (i.e. KKKK9) The 9 is known as a 'kicker' and will be decisive if more than one player share the four of a kind, then the one who has the highest kicker will win (55558 beats 55554).
Full house, three cards of one rank accompanied by two of another (i.e. QQQ22). Ranked by the triples, and then pair (55599 beats 444KK and 666AA beats 666QQ).
Flush, five cards of the same suit (i.e. 269JQ of spades). Ranked by the top card, and then by the next card, and so on for all five cards (A9652 beats KQJ73) Suits are not used to break ties, so tied pots are split.
Straight, five cards in sequence (i.e. 56789). The ace plays either high or low (AKQJ10 and A2345).
Three of a kind, three cards of the same rank (i.e. JJJ57). Ranked by the triples, and then ranked by the two kickers (55567 beats 444AK and 777Q2 beats 777J9).
Two pair, two cards of one rank, two cards of another rank and a kicker of a third rank (i.e. QQJJ8). Ranked by the top pair, then the bottom pair and finally the kicker (QQ775 beats JJ99A, KK336 beats KK22A and 9988K beats 99885).
One pair, two cards of one rank and three kickers of different ranks (i.e. 99345). Ranked by the pair, followed by the kickers from highest to lowest (77AKQ beats 77AKJ).
High card, if none of the above fits the hand, your highest card is the best you can do (i.e. 2367A).The top card is ranked first and so forth. Suits are not used to break ties, so tied pots are split.
 

Texas Hold´em
In Texas Hold’em each player is given 2 pocket cards. The game continues with a total of 5 community cards face up, first 3, then 1 after the other. Between each deal there is a round of betting.


Hold’em is played with two blinds (a bet before the pocket cards are received). The first two players after the dealer pay the blinds. The small blind is posted by the first player and the big blind by the second. In heads-up games, the player seated after the dealer pays the big blind. The first two betting rounds are played with the lower limit while the last two rounds of betting are played with the higher limit.

7 Card Stud
In Seven Card Stud, players are dealt seven cards throughout the course of the hand, but only the best five-card hand possible for each player is used to determine the winner.

Before a game of Seven Card Stud starts, all players ante a nominal amount, for example $1 in a $10-$20 game. Each player is dealt two hidden hole cards and one exposed card. The player with the lowest exposed card is the ''bring-in'', and is forced to make a wager of either a half a small bet or a full small bet (for example, either $1 or $2 in a $2/$4 game). Action continues clockwise around the table until betting is complete for the round.

In the unlikely event that all 8 players are still in the hand on the river, the total number of cards needed for all the players to receive their own card would not be available in a standard deck of cards. In this case the river card is dealt face up on the table and it will be used as a community card.

7 Card Stud Hi/Lo
The player with the best five-card hand for high wins half the pot, and the player with the best hand for low wins the other half. In the event that no hand qualifies for low, the best hand(s) for high wins the pot.

Omaha
Omaha is a poker game derived from Texas Hold’em. Each player is dealt four cards (''hole cards''), which belong only to that player. Five community cards are dealt face-up on the ''board''. All players use three of the five community cards together with two of their hole cards to make the best five-card poker hand.

Omaha Hi/Lo
The player with the best five-card hand for high wins half the pot, and the player with the best hand for low wins the other half. In Omaha, players must use two and only two of their four hole cards in combination with three cards from the board. In the event of identical hands, the high and low shares of the pot will be equally divided between the players with the best hands. In the event that no hand qualifies for low, the best hand(s) for high wins the pot.

For a five card hand to qualify for low, it cannot include cards higher than 8 or contain any pairs. Aces can be used for both high and low. When comparing low hands, the winner is the hand with the lowest high card, thus 3, 4, 5, 6, 7 is better than Ace, 2, 3, 4, 8. The best possible low hand is Ace, 2, 3, 4, and 5.