The four-leaf clover is an uncommon variation of the common, three-leaved clover. According to tradition, such leaves bring good luck to their finders, especially if found accidentally. In addition, each leaf is believed to represent something: the first is for faith, the second is for hope, the third is for love, and the fourth is for luck. There are approximately 10,000 three-leaf clovers for every four-leaf clover.
Don't forget that clovers can have more than four leaves and the most leaves ever found on a single clover stem is 56. And there is plenty of room for more "leaves" on this rest area ;)