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
History of the International Phonetic Alphabet closely connected that the whole might be treated as a single sound", were noted as able to be represented with a tie bar, as in . Palatalized consonants could be marked by a dot above the letter, as in , "suggesting the connexion with the sounds i and j". The 1921 "Écriture phonétique internationale" introduced new symbols, some of which were never to be seen in any other booklet: The book also mentioned symbols "already commonly used in special works", some of which "have not yet been definitively adopted": It also introduced several new suprasegmental specifications: It recommended the use