Quenya was J.R.R. Tolkien’s fictional Elvish language associated especially with the Noldor. Tolkien developed it as part of his larger system of invented languages and histories for Middle-earth.
Quenya was influenced in part by the sound and structure of languages Tolkien studied, including Finnish, Latin, and Greek, but it is not simply a translation code for any one real language. Its vocabulary and grammar developed over many years and changed as Tolkien revised his mythology.
Sindarin is the major neighboring Elvish language most often confused with Quenya. In Tolkien’s fiction, Sindarin was widely spoken in much of Middle-earth during the later histories, while Quenya had an older, more ceremonial status among many Elves. The two languages are related within the fictional history but are not interchangeable.