used to determine the winning hand and also for two hands (or maybe more) to tie. A kicker is a card that is part of the five-card poker hand, but is not used in determining a hand's rank. For instance, in the hand A-A-A-K-Q, the king and queen are kickers. The following situation illustrates the importance of breaking ties with kickers and card ranks, as well as the use of the five-card rule. After the turn, the board and players' hole cards are as follows. At the moment, Bob is in the lead with a hand of , making two pair, queens and eights, with a king kicker. This beats Carol's hand of by virtue of the king kicker. Suppose the final card is the , making the final board . Bob and Carol still each have two pair (queens and eights), but both of them are now entitled to play the final ace as their fifth card, making their hands both two pair, queens and eights, with an ace kicker. Bob's king no longer plays, because the ace on the board plays as the fifth card in both hands, and a hand is only composed of the best five cards. They therefore tie and split the pot. However, if the last card is a jack or lower (except an eight, which would make a full house, or a ten, which would give Carol a higher second pair), Bob's king stays in the game and Bob wins. Strategy Most poker authors recommend a tight-aggressive approach to playing Texas hold 'em. This strategy involves playing relatively few hands (tight), but betting and raising often with those that one does play (aggressive). Although this strategy is often recommended, some professional players successfully employ other strategies as well. Almost all authors agree that where a player sits in the order of play (known as position) is an important element of Texas hold 'em strategy, particularly in no-limit hold'em. Players who act later have more information than players who act earlier. As a result, players typically play fewer hands from early positions than later positions. Because of the game's level of complexity, it has received some attention from academics. One attempt to develop a quantitative model of a Texas hold'em tournament as an isolated complex system has had some success, although the full consequences for optimal strategies remain to be explored. In addition, groups