A raise in poker is an action whereby the player increases the size of the current bet. A raise allows the player to increase the amount of money which other players need to add to the pot to remain in the round. This is one of the basic actions in poker and may be used for various purposes:

Increasing a bet: The player may decide to increase the size of their bet in order to increase the size of the pot and create more profitable conditions for themselves.

Bluffing: A raise may be used as a bluff. The player may raise by a high amount to force their opponents to fold by creating the impression of having a strong hand, even if their hand is not very strong in reality.

Defending: A player may raise in response to an opponent’s bet in order to defend their hand or to find out how strong the opponent’s hand is.

Family: Sometimes, players use a raise to increase the size of the pot and increase the chances of getting a winning hand on the last community cards (turn and river).

A raise may be any amount, but usually it should be at least equal to the minimum bet (blind) or the previous raise, if there is one. After a raise, other players can call (match bets), increase the bet (raise), or discard their cards (fold), depending on their strategy and the cards in their hand.