Freebird

Today I read a recipe on line that called for "one free-range egg."
How exactly does an egg free range?
Does the farmer have to carry the egg outside and manually roll it around in the grass?
I can just hear the egg shouting (it's got the voice of Gilbert Gottfried), "Wheeeeee! Look Ma! I'm free ranging!"

song: Freebird • artist: Lynyrd Skynyrd