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 abbreviations Morse code are formed. From 1845 until well into the second half of the 20th century, commercial telegraphic code books were used to shorten telegrams, e.g. "Pascoela = Natives have plundered everything from the wreck". The following Table of Morse code abbreviations and further references to Brevity codes such as the Q code, Z code and R-S-T system serve to facilitate fast and efficient Morse code communications. To make Morse code communications faster and more efficient, there are many internationally agreed patterns or conventions of communication which include: extensive use of abbreviations, use of brevity codes such as the RST