In U.S. tax law there is a distinction between gifts and windfalls. A windfall — historically referring to fruit or trees blown down by the wind which then become public property — now refers to any sudden, unearned gain such finding money on the street or buried treasure. A gift, however, is a gain given by a donor and motivated by generosity, affection, respect or the like. A key distinction is that the recipient of a windfall is taxed, while the recipient of a gift is not.