Quenya is the invented language associated with the High Elves in J.R.R. Tolkien’s legendarium. Tolkien developed it with strong influences from Finnish, Latin, and Greek, while giving it its own grammar, vocabulary, and historical evolution.
Within the fictional history, Quenya was used by the Ñoldor and other peoples descended from the Eldar. It became a formal, literary, and ceremonial language in Middle-earth, rather than the everyday speech of most Elves in the later ages.
Sindarin is the most common source of confusion because it is another major Elvish language and appears frequently in The Lord of the Rings. Tolkien treated Quenya and Sindarin as related languages with different histories, sounds, and social roles.