ISMN is an acronym for the International Standard Music Number and was designed in 1952.
 Acronyms are usually formed from the initial letters of words, as in NATO (North Atlantic Treaty Organization), but sometimes use syllables, as in Benelux (short for Belgium, the Netherlands, and Luxembourg), NAPOCOR (National Power Corporation), and TRANSCO (National Transmission Corporation)
 Specifically, each digit of the ISMN is multiplied by a weight, alternating 1 and 3 left to right

