set. It is intended for data and command interchange among chessplaying programs. It is also intended for the representation of portable opening library repositories. It is better than FEN for certain chess variants, such as Chess960. Notation for telegraph and radio Some special methods of notation were used for transmitting moves by telegraph or radio, usually using Morse Code. The Uedemann code and Gringmuth notation worked by using a two-letter label for each square and transmitting four letters – two letters for the origin square followed by two letters for the destination square. Castling is shown as a king move. Squares are designated from White's side of the board, files from left to right and ranks from nearest to farthest. The Rutherford code first converted the move into a number and then converted the move number into a composite Latin word. It could also transmit moves of two games at the same time. Uedemann code This code was devised by Louis Uedemann (1854–1912). The method was never actually used, mainly because a transposition of letters can result in a valid but incorrect move. Many sources incorrectly use this name for the Gringmuth code. The files are labeled "A", "E", "I", "O", "O", "I", "E", and "A". The ranks are labeled "B", "D", "F", "G", "H", "K", "L", and "P". A square on the is designated by its file letter and then its rank letter. A square on the is designated by its rank letter then its file letter. Gringmuth notation This method was invented by Dmitry Alexeyevich Gringmuth but it is sometimes incorrectly called the Uedemann Code. It was used as early as 1866. Files were designated with one of two letters, depending on whether it was on White's side or Black's side. These letters were: B and M, C and N, D and P, F and R, G and S, H and T, K and W, L and Z. Ranks were labeled: "A", "E", "I", "O", "O", "I", "E", and "A". Rutherford code This code was invented in 1880 by Sir William Watson Rutherford (1853–1927). At the time, the British Post Office did not allow digits or ciphers in telegrams, but they did allow Latin words. This method also allowed moves for two games to be transmitted at the same time. In this method, the legal moves in the position were counted using a system until the move being