Tengwar is the Elvish script J.R.R. Tolkien used for writing Quenya.
Tengwar, also called the Fëanorian characters, is a writing system created by Tolkien for the languages of Middle-earth. It was designed to represent sounds rather than function as a single language. Quenya, Sindarin, and other languages could therefore be written with Tengwar using different spelling conventions.
The script is associated with Fëanor, the great craftsman of the Elves, and its name is derived from a Quenya word meaning letters or signs. Tolkien’s illustrations and examples helped establish its recognizable forms, including consonant letters and vowel marks called tehtar.
Cirth is a different Tolkien script, made from angular runes and especially associated with the Dwarves. Sarati is an earlier script in Tolkien’s invented writing history. Those distinctions make Tengwar the specific answer here.