In every culture there's different beliefs about fairies. In one culture it said they are a race of beings betweens humans and spirits. In another culture it said that they are the ones who bestow peoples destiny. I personnally believe that they are spirits that look after woods and wild places kind of like nymphs
There are SOOOO many type of fae. Some are brownish and have pointed ears and wrinkly faces (brownies, I call them), some have wings and are pretty and sparkly (and nekkid)--these are the ones that tease my cats, some have wings and are nasty with big teeth, some are human sized, some are the size of a small child, some are like shadow people.
There are TONS of different fae from all different cultures. It's best to pick up mythological books to read about Them.
From a elemental stand point there are the air faeires who live in high moutins or deep desert,earth faeires whose I have yet to see,water faeires mostly spend their time tending to water palnts they sorta resemble dragonflys. They arnt likely to interact with humans, fire faeries they are tricky they can help with shapeshifting (astraly) out of the 4 types of elementals faeries the fire faeire is the most like to interact with humans. This info came from a book called elemental magick.
PLEASE don't read DJ Conway! Her historic research is non existent. Her "Celtic Magic" and "Norse Magic" books are nearly carbon copies of one another, and neither has anything to really do with the Celts OR the Norse.
Here are good links about the Fae:
The word 'faery' is a general term for any nature spirit. Some live in the astral plane, others in the physical plane. The stereo-typical fairy is traditionally called a sylph and I think it was renamed fairy from the fact that it's an 'airy spirit' and an 'f' was added in after hearing the word 'faery' during the scientific revolution but not seeing its actual spelling. By the way, Conway's books are usually alright but I'd the best by far is her magickal, mystical creatures book. That has a HELL of alot of fact in it.
the word "fearie" comes from "Fae" meaning "fate" (or destiny) and is beleived to have been first used by the Northern Tribes as a title to describe the three "Wyrd Sisters" who sit beneath the world tree and weave the destiny of man.
but the legends and stories of the little people span back into all culture right back into the history of all lands.
Some think that they are Nature Spirits (elementals) that protect,guide the forces of Nature.
others have said that they are a race from the Otherworld who cross into this realm to help (or hinder) our lives
one legend speaks of an lost race that came to the shores after their land sank into the ocean where another says they may of beeen the caveman like people that lived in the Britsih Isles before the celts settled there.
wherever they came from or who they are what is sure is that our ancestors beleieved in them very much and respected them alot.