J.R.R. Tolkien created Quenya as the language of the High Elves.
Quenya is one of Tolkien's most fully developed constructed languages. Its sound and structure were influenced especially by Finnish, while its vocabulary and history belong to Tolkien's invented world. In the mythology, Quenya developed from the speech of the Elves who undertook the Great Journey and became associated with the Ñoldor and other Eldarin peoples.
Sindarin is the other major Elvish language encountered in The Lord of the Rings. Tolkien based its sound partly on Welsh, and it is generally the more commonly spoken Elvish language in the Third Age. Quenya survives in formal, poetic, and historical use among characters such as Galadriel and the High Elves.
The languages are sometimes treated as interchangeable, but they have different histories and roles. Tolkien studied real languages professionally and designed his invented tongues with related vocabularies, sound changes, and grammatical development rather than as simple word lists.