Everything Else .
Gnats bother people because they are hungry.
Generally, it refers to any of the many swarming little two-winged flies, members of the order Diptera, or true flies, that may collide with human eyes, ears, noses and skin. There are regional differences in meaning. In the North, gnats are generally considered to be biting black flies in the family Simuliidae, humpbacked gluttons looking for a blood meal. In the South, gnats are even smaller nonbiting flies of several species in the family Chloropidae. They feed on secretions of the eye and nose and spread pink eye, or conjunctivitis.