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
International Code of Signals One simply raises the Kilo flag (see diagram at the top), or sends the Morse Code equivalent (dash-dot-dash) by flashing light; this has the assigned message of "I wish to communicate with you." One practical application of the ICS is that all of the standardized messages come in nine languages (English, French, Italian, German, Japanese, Spanish, Norwegian, and, since 1969, Russian and Greek). This fact is immaterial if the sender and receiver(s) are using different languages; each language has a book with equivalent messages keyed to the same code. This is also useful in radiotelephony, or even when ships are