The table, the button and the blinds

A 6-max table has six seats named by where they sit relative to the dealer Button: Lojack, Hijack, Cutoff, Button, Small Blind, Big Blind. The button moves one seat left every hand, so everyone takes turns in every position.

Nobody would ever bet if there were nothing to win, so the two players left of the button post forced bets before the deal: the small blind (half a unit) and the big blind (one unit). Everything is measured in big blinds. In a $1/$2 game, "raise to 7 BB" means $14. Stack sizes are quoted the same way: sitting with $200 in a $1/$2 game is "100 big blinds deep," which is the buy-in this whole app assumes.