Page "Danish language" Paragraph 4

Old East Norse is in Sweden called Runic Swedish and in east Denmark Runic Danish, but until the 12th century, the dialect was roughly the same in the two countries.

The dialects are called runic because the main body of text appears in the runic alphabet.

Unlike Proto-Norse, which was written with the Elder Futhark alphabet, Old Norse was written with the Younger Futhark alphabet, which only had 16 letters.

Due to the limited number of runes, some runes were used for a range of phonemes, such as the rune for the vowel u which was also used for the vowels o, ø and y, and the rune for i which was also used for e.