The Cirth ("Runes") are the letters of an artificial script which was invented by J. R. R. Tolkien for the constructed languages he devised and used in his works.
In the fictional history of Middle-earth, the original Certhas Daeron was created by Daeron, the minstrel of king Thingol of Doriath and was later expanded into what was known as the Angerthas Daeron. Although the Cirth were later largely replaced by the Tengwar (which were enhanced and brought by Fëanor), they were adopted by Dwarves to write down their Khuzdûl language (Angerthas Moria and Angerthas Erebor) because their straight lines were better suited to carving than the curved strokes of the Tengwar. Some examples of Cirth writings are the inscription on Balin's tomb in Moria and the inscriptions on the top of the title pages for The Lord of the Rings. Cirth was also adapted, in its older and simpler form, by various kinds of Men and even Orcs. For example, it was used by the Men of Dale and the Rohirrim and the Orcs of Moria.