Tally marks

Numeral form used for counting

Tally marks, also called hash marks, are used as a basic numeral system for counting; they can be thought of as a unary numeral system. They are most useful in counting (tallying) ongoing results, such as the score in a game or sport, as no intermediate results need to be erased or discarded. However, because of the length of large numbers, tallies are not commonly used for static text.

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