Iceland's official written and spoken language is Icelandic, a North Germanic language descended from Old Norse. In grammar and vocabulary, it has changed less from Old Norse than the other Nordic languages; Icelandic has preserved more verb and noun inflection, and has to a considerable extent developed new vocabulary based on native roots rather than borrowings from other languages. The puristic tendency in the development of Icelandic vocabulary is to a large degree a result of conscious language planning, in addition to centuries of isolation. Icelandic is the only living language to retain the use of the runic letter Þ in Latin script. The closest living relative of the Icelandic language is Faroese.