Fae aka Faeries have many different names. Some can see them in this realm, some cannot. There are many different types and different beliefs of them, depending on which culture you are from.
Grg, there is a kind that appears as a little ball of light. To some this is known as a "sylph".
If you would like an interesting read, search these terms below:
Fae, faery, Tuatha De Dannan, Sidhe, fair folk, Dryads...