Tradition has it that leprechauns are mischievous little people, often cobblers, with pots of gold hidden away.
Humans are always keen to find the gold, of course, but are outwitted by the leprechauns' cunning and magical powers.
In all of the six tales, humans are taught a lesson by the little people, whether as a result of overwhelming greed for the gold, picking flowers where flowers are not supposed to be picked, or merely not believing in leprechauns.