A rune is a letter in a set of related alphabets, known as runic rows, runic alphabets or futharks (also, see futhark vs runic alphabet), native to the Germanic peoples of the 1st millennium and beyond. Runes were used to write Germanic languages (with some exceptions) before they adopted the Latin alphabet, and for specialised purposes thereafter. In addition to representing a sound value (a phoneme), runes can be used to represent the concepts after which they are named (ideographs). Scholars refer to instances of the latter as Begriffsrunen ('concept runes').
https://en.wikipedia.org/wiki/Rune