Definition of split
A split is when a pot is separated. A pot can be split for two reasons: when 2 players have the same hand at the showdown or when playing a high-low variant, i.e. a variant in which you often play for two halves of the pot, one half you win when you make the best high and one half you win when you make the best low. In high only variants, if 2 or more players have the same hand, the pot is split equally. A split pot can also occur when the board gives everyone the best hand (for example if a board gives T-J-Q-K-A and there is no flush).
What if the prize pool is not divisible by 2?
Let's say you are playing heads-up with a player. You come to the showdown on a 2-2-5-5-7 board and both of you have AK. This is a split pot. But the pot is $10.11, a number that doesn't split two (well, yes, but $0.01 is the smallest unit of currency). What do we do? We deal 5.05 to each player and the excess ($0.01) goes to the player who was out of position postflop.
