Being an Elf from Tolkien's Books

In J. R. R. Tolkien's legendarium, an Elf is an individual member of one of the races that inhabit the lands of Arda. They appear in The Hobbit and in The Lord of the Rings, but their complex history is described in full only in The Silmarillion, edited and published after Tolkien's death. More details about them are given in the author's other writings edited and published since then, such as Unfinished Tales and The History of Middle-earth. The History of Middle-earth also reveals their textual and conceptual history, as Tolkien had been writing about Elves long before The Hobbit was published.

From Wikipedia