The Joint Army/Navy Phonetic Alphabet was a radio alphabet developed in 1941 during World War II and was used by all branches of the United States Armed Forces until the promulgation of the ICAO spelling alphabet (Alfa, Bravo) in 1956, which replaced it. Before the Joint Army/Navy (JAN) phonetic alphabet, each branch of the armed forces used its own radio alphabet, leading to difficulties in interbranch communication. The U.S. Army used this alphabet in modified form, along with the British Army and Canadian Army from 1943 on, with "Sugar" replacing "Sail".