Little Bugs ?

Question

What are those bugs that fly in groups, their like the size of a mosquito - yet they are in groups of hundreds, usually hovering over a grass patch - and their very small and very fast motioned. They cause no harm to me, but when I walk thru them they sometimes follow me for a second. What are they ??

Answer 1

Swarms of gnats

Answer 2

Gnats.

Answer 3

Gnats!  Irritating little buggers aren't they.

Wikipedia says the males often assemble together in large mating swarms, particularly at dusk, called a "ghost".