Letter (alphabet) of sounds to make words. A letter is classed as either a consonant or a vowel, depending on how its sound is produced (vowels are "a", "e", "i", "o", "u", and sometimes "y" and "w"). The basic Roman alphabet is used by about one hundred languages, with slight variations. Some versions contain as few as twenty-one characters, some as many as thirty. Letters have specific names associated with them, which may differ with language, dialect, and history. "Z", for example, is usually called "zed" in all English-speaking countries except the US, where it is named "zee". As elements of alphabets,
American Morse code Most radio operators used the version of the Code that they were most familiar with—the American Morse Code in the United States, and Continental Morse in Europe. However, because of the long range of radio signals, a single international standard was needed, especially for seagoing vessels. At the Radiotelegraphic Convention meeting in London in 1912, the section of the Convention covering "Transmission of Radiograms" included the statement that "The signals to be employed are those of Morse International Code." Even after this, the original Morse Code continued to be used throughout much of the United States. American Morse remained the