Runes
The Runes are an ancient Germanic alphabet used for writing and divination. The oldest known runic alphabet is the Elder Futhark, with 24 runes, used between the 2nd and 8th centuries by Germanic peoples. Modern runic divination was systematized in the 19th-20th centuries by occultists like Guido von List (Armanen runes, 1908).
Three aetts
The 24 runes are divided into three groups of 8, called aetts: Freyr\'s aett, Heimdall\'s aett, Tyr\'s aett.