The invented script used to write many Elvish texts in J.R.R. Tolkien’s works is Tengwar.
Tengwar is a writing system created by the Elf Fëanor in Tolkien’s fictional history. Its letters, called tengwar, are arranged with a system that represents consonants and vowels through signs and tehtar. The exact values can vary according to the language being written.
Tolkien used Tengwar for languages including Quenya and Sindarin, and the script also appears in inscriptions connected with the One Ring and other objects. Its elegant forms have made it one of the most recognizable visual elements of Tolkien’s world.
Tengwar is a script, not a language. Cirth is another writing system, characterized by angular runes, while Sarati is an earlier script in Tolkien’s mythology. Angerthas refers to an expanded runic arrangement associated with Cirth.