In contrast to limit games, no-limit games have no limit on the number or size of bets that can take place, except for the size of a player's stack. Players can bet any amount from the minimum bet size to the maximum "all-in" bet, where they bet the remainder of their stack.
In No-limit Texas Hold'em, the nominal minimum bet size is either the size of the big blind at the beginning of a round or the size of the most recent bet. If the nominal minimal bet is larger than the maximum bet, then the minimum bet is equal to the maximum bet. If someone has already made the maximum "all-in" bet, then you cannot raise. For the competition, raises must be of an integer number of chips.
Doyle's Game is a variant of no-limit Texas Hold'em where players can make an "all-in" bet, but a player's stack size is reset to some default size after every hand and the score is kept separately. For example, when playing Doyle's Game with stacks 1000 times the size of the small blind, the maximum amount to be put in the pot by a player in a hand is 1000 times the small blind. Regardless of a player's current stack size, upon starting the next hand, their stack size is set to be 1000 times the size of the small blind. This is akin to both players buying in for 1000 small blinds every hand, cashing in their chips at the end of the hand, and buying in for 1000 small blinds again the next hand.
Resetting stacks in this manner prevents two problems: