This is Iro from Wikipedia (I don't know why the accounts don't transfer) and I'm going to expand the definition with three subsections:
Norse Alfar (Ljosalfar)
English folkloric Elves
Fantasy elves taken after Tolkien's Eldar (which, for all intensive purposes, were Alfar)
- Hm, wouldn't they be written with an acute accent? E.g. Singular: [ljós]álfur, plural: [ljós]álfar? --BiT 14:30, 30 November 2007 (UTC)
The original (and still valid) plural of Elf is elfs. The common (fantasy) plural is elves which was coined by J.R.R. Tolkien. I'm not certain where to put this information so I'm leaving a note for anyone who has a better grasp of the page structure.