Button: The dealer (D), or the dealer position in the case of a casino dealer or other fixed dealer, is indicated by a button. This player is the last to act in each betting round after the flop.
Blinds: Before each hand, the two players to the immediate left (clockwise) of the dealer must put in bets before the cards are dealt. The Small Blind (SB) is one position to the left of the dealer except in heads-up play, where the dealer is the Small Blind. The Big Blind (BB) is two to the left of the dealer except in heads-up play, where the non-dealer is the Big Blind. The Small Blind is usually half as much as the Big Blind amount.
Antes: A game's rules may also include an ante, a bet placed into the pot before each hand by all players before the cards are dealt. This is in addition to the blinds for those two players.
Minimum Bets: The player to the left of the Small Blind acts first and may either fold (quit the hand by putting his cards face down in the middle of the table), call the Big Blind (match the amount of the Big Blind), or raise. The minimum raise is to twice the previous raise, so initially this is twice the Big Blind. On subsequent betting rounds, the minimum opening bet resets to the size of the Big Blind. [On THETA Poker's Raise screen, bets are rounded to an even chip amount and raised to the minimum if too low.]
Maximum Bets: The three main variations of Texas Hold 'Em are distinguished by their maximum bets. Limit Hold 'Em specifies an exact maximum for all bets and raises. This is usually one amount pre-flop and on the flop and a higher amount on the turn and river. Pot Limit Hold 'Em allows bets up to the current size of the pot. No Limit Hold 'Em allows any bet (up to all of the player's chips) at any time. [THETA Poker currently implements No Limit Hold 'Em only.]
Maximum Re-Raises: Up to three re-raises (the opening bet plus three raises) are allowed in each betting round [configurable option].
Winning the Pot: If at any time during a hand, all but one player has folded, the remaining player wins all of the chips in the pot. Otherwise, the hand proceeds to the showdown after betting on the river. The player with the highest valued five-card poker hand wins the pot. In the event of a tie, the spot is split evenly, with the odd chips given to the player[s] closest to the Small Blind moving clockwise away from the Button. [See Poker Hand Values for the rank of poker hands.]
Ending the Game: The game ends when you lose all your chips or you win all of everyone else's chips. [THETA Poker also allows you end the current game at any time by shaking your iPhone or iPod touch or selecting New Game from any options screen.]