The script J.R.R. Tolkien devised for writing many of the Elvish languages is Tengwar.
Tengwar is a writing system used in Tolkien’s fictional world for several languages, including Quenya and Sindarin. Tolkien designed its letters so that their forms and sound relationships followed an internal system rather than functioning as decorative symbols alone.
In Middle-earth, the Elf Fëanor is credited with devising the script during the First Age. Tolkien’s appendices and other writings describe how Tengwar could be adapted to different languages and pronunciation systems. This flexibility distinguishes a writing system from a language: Tengwar is the script, while Quenya and Sindarin are languages.
Cirth is the main alternative readers often confuse with Tengwar. Cirth uses angular runes and was associated especially with Dwarves, although other peoples also used it. Tolkien also created earlier scripts, including Sarati, so Tengwar is not his only invented writing system.