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
Morse code abbreviations code, Q code, Z code as well as the use of Morse prosigns. The skills required to have efficient fast conversations with Morse comprise more than simply knowing the Morse code symbols for the alphabet and numerals. Skilled telegraphists must also know many traditional International Morse code communications conventions. In the following example of a typical casual Morse code conversation between two stations there is extensive use of such: Morse code abbreviations, brevity codes, Morse procedural signs, and other such conventions. An example casual Morse code (CW) conversation between Station S1 and Station S2 is illustrated in the following paragraphs.