Runes is a kind of extinct letters, which is used to form the language of Rune and to write some Nordic Germanic languages in medieval Europe, especially in Scandinavia and the British Isles. The rune used in Scandinavia is called futhork, and the rune used in Britain is called Futhorc, which has a strong religious flavor.

In Nordic mythology, Odin, the father of the gods, in order to get the fountain of wisdom, he lost one right eye in exchange for the wisdom of Lu en. Runes is a kind of mantra. If you engrave it on wood, stone, metal or any other material, you can get infinite power. In order to seek higher wisdom, Odin hung himself on a tree for nine days and nine nights, thinking about the mysteries of the universe.

Source: @electricartfoxlake