J.R.R. Tolkien starts to create this elven language in 1915 (before starting to create "Lord of the Rings"). Base of this language is Latin, but Tolkien wanted to create as beautiful a language as possible, so it sounds much better.
Anyway in the 3rd epoch, when "Lord of the Rings" events had place, this language was not used same as not use Latin in our time. This language is only language of science and art in this time.
How this language is called?