Poker Glossary

A re-raise pre-flop. The first voluntary raise (by the open-raiser) is a 2-bet because the blinds count as the 1-bet. A 3-bet is the next raise on top of that. 3-betting is how you put maximum pressure on weak ranges and isolate strong hands.

Postflop bets plus raises divided by postflop calls. Measures how aggressive a player is after the flop. AF below 1 is passive. AF above 3 is hyper-aggressive. Combined with VPIP and PFR, it completes a basic opponent profile.

A bet on the turn or river following a c-bet on the flop. A two-barrel is c-bet flop + bet turn. A three-barrel is c-bet flop + bet turn + bet river. Barreling maintains pressure across streets and maximizes fold equity against marginal hands.

A bet on the flop by the player who raised pre-flop, regardless of whether they connected with the board. C-betting is the default aggressive line in heads-up pots because the pre-flop aggressor often wins the flop unchallenged.

An iterative algorithm for computing approximate Nash equilibrium strategies in imperfect-information games. CFR is the foundation of every top professional poker AI, including Libratus and Pluribus.

Checking to give your opponent the chance to bet, then raising their bet. Check-raising traps aggressive opponents, builds bigger pots for value, and occasionally functions as a powerful bluff against c-betting-happy opponents.

Your probability of winning the hand at showdown, expressed as a percentage. Equity is the input to every pot odds and expected value calculation. A hand with 40 percent equity wins 4 times out of 10 against its opponent range.

The average chip outcome of a decision across all possible results, weighted by probability. A +EV decision gains chips on average over many repetitions; a -EV decision loses them. Every poker bot decision should maximize expected value.

Calling a c-bet with a weak hand, planning to take the pot away on a later street by betting when the opponent shows weakness. Floating works against predictable c-bettors who give up on the turn when they have nothing.

The portion of your bet's expected value that comes from your opponent folding, rather than from winning at showdown. Fold equity is why bluffs are profitable and why bet sizing matters: a bigger bet forces more folds but risks more chips.

The idea that you need a stronger hand to call a raise than you need to open the pot yourself. The gap exists because calling has less fold equity and gives the opener range advantage.

A strategy that cannot be exploited by any opponent, regardless of how they play. GTO is the theoretical ceiling of defensive play. Against perfect opponents, GTO breaks even. Against imperfect opponents, it leaves money on the table compared to exploitative play.

A mathematical model that converts tournament chip stacks into expected prize money. ICM matters in tournaments because each chip is worth less than the last, which changes optimal strategy compared to cash games where every chip has equal value.

The expected future chips you will win on later streets if you hit your draw, beyond the chips currently in the pot. Implied odds extend pot-odds math to account for the money you expect to make after the draw completes.

A playing style that plays many hands (loose) with frequent raising and betting (aggressive). LAG has the highest ceiling of any style because it pressures opponents constantly, but it is the hardest to execute without bleeding chips.

A player who only plays the strongest hands and folds everything else. Nits have very low VPIP (often under 12 percent) and rarely bluff. They are safe to play against but leave money on the table by folding too much.

The percentage of hands where a player open-raised or re-raised pre-flop. In poker PFR is paired with VPIP to show how aggressive an opponent is and expose the gap between hands they play and hands they play aggressively.

Where you act in the betting order relative to the dealer button. Late position (button, cutoff) acts after opponents and has an information advantage. Early position (UTG, HJ) acts first and should play tighter. Position is worth 0.5-1 bb/100 on its own.

The ratio between the current pot size and the cost of a call. Pot odds tell you what win probability you need to call profitably. If your estimated equity exceeds the pot odds, calling is +EV.

The size of your remaining stack divided by the pot at the start of postflop play. SPR tells you how much commitment your hand needs to be worth. Low SPR means stack-off with one pair. High SPR means protect your stack with all but the nuts.

A playing style that plays a narrow range of hands (tight) but plays them aggressively when involved (aggressive). In poker, TAG is the standard baseline for competent bot strategies: VPIP around 18-22 percent, PFR around 14-18 percent.

The strongest possible hand given the current board. On an A-K-7 rainbow flop, the nuts is a set of aces. The nuts is the hand no other hand can beat, and it changes as new community cards are dealt.

A made hand where you pair the highest card on the board and hold the best possible kicker. TPTK is strong enough to value bet many flops, but it is not a stack-off hand at deep SPR.

The percentage of hands where a player voluntarily put chips into the pot pre-flop. Does not count blinds that are never called or raised. The fastest single-stat read of whether an opponent is tight or loose.