In Lowball, each player gets five private cards, may discard and replace, and the lowest hand wins.
Variants:
California Lowball A-5 (Ace-to-Five) - Straights and Flushes don't count and Aces are low. Best hand is A-2-3-4-5. Best for home games.
Triple Draw Lowball 2-7 (Two-to-Seven) - You have three rounds of discarding and drawing, straights and flushes count against you and Aces are high. Best hand is 2-3-4-5-7 unsuited. Version played in casinos, mixed games and WSOP events.