blind

The blinds are forced bets posted by players to the left of the dealer button in flop-style poker games. The number of blinds is usually two, but it can range from none to three.
The small blind is placed by the player to the left of the dealer button and the big blind is then posted by the next player to the left. The one exception is when there are only two players (a "heads-up" game), when the player on the button is the small blind, and the other player is the big blind. (Both the player and the bet may be referred to as big or small blind.)
After the cards are dealt, the player to the left of the big blind is the first to act during the first betting round. If any players call the big blind, the big blind is then given an extra opportunity to raise. This is known as a live blind. If the live blind checks, the betting round then ends.
Generally, the "big blind" is equal to the minimum bet. The "small blind" is normally half the big blind. In cases where posting exactly half the big blind is impractical due to the big blind being some odd-valued denomination, the small blind is rounded (usually down) to the nearest practical value. For example, if the big blind in a live table game is $3, then the small blind will usually be $1 or $2 since most casinos do not distribute large quantities of $0.50 poker chips.
The blinds exist because Omaha and Texas hold 'em are frequently played without antes, allowing a player to fold his hand without placing a bet. The blind bets introduce a regular cost to take part in the game, thus inducing a player to enter pots in an attempt to compensate for that expense.
It is possible to play without blinds. The minimum bet is then the lowest denomination chip in play, and tossing only one chip is considered as a call. Anything higher than that is considered a raise. Poker without blinds is usually played with everyone posting an ante to receive cards.

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