In most "low" poker games the hand rankings are usually as follows (with flushes and straights not being counted).

No Pair - In "low" games the best hands to make are the straight or the flush (as these don't count) therefore you have single cards in your hand. Other hands are ranked in a reverse order from those used in normal poker. To determine a winner the highest cards in the hands are compared and the lowest ranking card wins. If the highest cards are of equal rank, the next highest cards are compared with the lowest ranking card winning. If again these cards are equally ranked the next highest cards are examined, the cards are compared one pair at a time until a winner is determined, the hand with the lowest value wins.

Examples: 9-8-6-3-2 beats 9-8-6-5-3 (the 3 is a lower value than the 5).
Q-10-5-4-A beats Q-10-5-4-2 (the A is a lower value than the 2).
8-6-5-3-2 beats 8-7-5-3-2 (the 6 is a lower value than the 7).

One Pair - When two players have a hand with a pair, the hand with the lowest value pair wins. If the pairs are equal, you compare cards from the highest valued card in each hand with the lower value card winning. In the event that the cards are of equal value the next highest card is compared and so on until the winner is determined by virtue of it having the lowest ranking card, or the hands are determined to have the same cards in them.

In using tie breaker rules "Low Hand" games use the same method as normal versions of poker, with the exception that the rankings are reversed so the lower value card wins.

In some "Low Hand" games Flushes and Straights are counted and the Aces are counted normally (as high ranking cards). One such game is called Deuce to Seven Triple Draw. This game has the best hand being 2-3-4-5-7 (the lowest value straight) thus the name of the game.