Humans as a species love classifications, because if someone can classify something, they feel like they can understand it. In some of his famous works about faeries, Irish author William Butler Yeats described two types of faeries: Trooping and Solitary. Later, Katharine Mary Briggs added a third category for Domestic Faeries.
Trooping Faeries were those that would travel in large troops, which lent them their name. They also were known for holding grand balls and parties and generally wanting to have a good time. They were normally pretty friendly to humans, as long as they were properly respected.
Solitary Faeries were faeries that lived on their own. These faeries tended to be more outright nasty towards humans, some eating humans or keeping them as pets. However, some of them were just mischievous and not necessarily harmful.
Domestic Faeries were faeries that lived in the houses of humans. Many of these faeries were actually helpful to the humans they lived with, as long as they were properly respected.
Image From: Fine Art America