Letter frequency xz. Modern International Morse code (generally believed to have been developed by Alfred Vail based on English-language letter frequencies of the 1830s) encodes the most frequent letters with the shortest symbols; arranging the Morse alphabet into groups of letters that require equal amounts of time to transmit, and then sorting these groups in increasing order, yields e it san hurdm wgvlfbk opxcz jyq. Similar ideas are used in modern data-compression techniques such as Huffman coding. Letter frequency was used by other telegraph systems, such as the Murray Code. Letter frequencies, like word frequencies, tend to vary, both by writer and
Telegraph code limited character set available in Baudot code. Demand for lowercase letters and more punctuation marks led to teleprinters with a 6-bit TeleTypeSetter (TTS) code, and later, 7-bit ASCII code. In 1931, the International Code of Signals, originally created for ship communication by signalling using flags, was expanded by adding a collection of five-letter codes to be used by radiotelegraph operators. Telegraph code A telegraph code is one of the character encodings used to transmit information through telegraphy machines. The most famous such code is Morse code. Morse code can be transmitted and received with very simple electrical equipment, such as