This article is about the categorization. For a list of species classified as Grays, see Category: Grays.
Grays are an unscientific grouping of slender humanoid species with large eyes and craniums. Their skin is usually some shade of gray or green, hence the name (get it?), although yellow, purple, red, and blue also occur. Although the grouping is unscientific it's still likely that most of them share a common ancestry. As often as not the term refers specifically to Reticulon Grays, who are by far the most prolific and have appropriated the term for themselves without concern for anyone else who might want to use it. For example, they are the only members of the Gray Federation.