The document discusses the history and development of the International Civil Aviation Organization (ICAO) phonetic alphabet. It notes that the ITU first adopted an international alphabet in 1927 which was used for civil aviation until WWII. During the war, the USAAF and RAF developed their own codes which were later merged in 1943 and adopted for civilian aviation after the war. In 1947, the ICAO adopted a new alphabet to incorporate common sounds in Spanish, English, and French, though some letters were later changed in 1956 to address problems. The document then lists the letters and numbers of the ICAO alphabet as well as providing the Swedish equivalents.