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,
Morse code is 60 milliseconds. Using the word CODEX with 60 dot units, the dot length at 20 words per minute is 50 milliseconds. Because Morse code is usually sent by hand, it is unlikely that an operator could be that precise with the dot length, and the individual characteristics and preferences of the operators usually override the standards. For commercial radiotelegraph licenses in the United States, the Federal Communications Commission specifies tests for Morse code proficiency in words per minute and in code groups per minute. The Commission specifies that a word is 5 characters long. The Commission specifies Morse code