Definition:Roman Numerals

The Roman numerals are:

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To express other numbers than these, symbols are placed next to each other so as to cumulate: e.g. II means "two", CCXVI means "two hundred and sixteen".

For brevity in presentation, the technique is used of placing a smaller denomination in front of a larger one so as to subtract the former from the latter, e.g. IV means "four", XCIX means "ninety-nine" (although IC could be used, it isn't).

The Roman numerals are used today solely for enumeration in certain traditional contexts, for example the writing of dates, especially the date of the construction of buildings.

Arithmetic using roman numerals is cumbersome and pointless, although some grade-school arithmetic texts insist on setting such operations as exercises.

For doing arithmetic, abacism was the usual technique, originating in ancient times. It is still used in rural areas of, for example, the Asian steppes, where writing materials are not to be wasted and electronic aids are un-needed.

With the invention of the techniques offered by the so-called Arabic numerals in mediaeval times, an alternative method of doing arithmetic developed, called algorism.