It generally refers to the initial action or bet made by the first player to act in a particular betting round.
- Open Raise: it's the first voluntary bet made in a betting round, typically preflop. It's when a player initiates the betting by raising the stakes before any other player has placed a bet in that round. For instance, if no one has raised before, the player who makes the first raise is executing an open raise. This move often signifies strength or an attempt to take control of the hand.
- Open Limp: it occurs when a player enters a hand by merely calling the minimum bet instead of raising or folding. It's essentially limping into the pot as the first player to enter, indicating a more passive approach to the hand. An open limp is different from an open raise because it involves entering the hand without raising the stakes. Players who open limp usually have a weaker or speculative hand and prefer to see more cards before investing further in the pot.