A low card, especially a 5 or less, useful for making a low hand.
A useless card that cannot form part of a low hand. E.g. a 9 or higher card in an 8-or-better game.
Getting a card that will likely let you split the pot.
Two consecutive cards that improve a player's hand.
Winning the entire pot, either with the best high hand where there is no low, or by having both the best high and low hands.