Unary numeral system
The Unärsystem is an addition system that has only a symbol with the value 1. Each one is represented by the same symbol, usually by a vertical bar: 810 = | | | | | | | | unary.
Practical Application
The Unärsystem is suitable for simple counting tasks, since increasing a number by 1 by simply appending an additional symbol is happening. It has been used for example as a tally sheet, in which every fifth line is drawn across the four previous times for readability. The resulting number is represented as grouped in five blocks, and thus more easily manageable.
In addition, the Unärsystem is sometimes used in computer science, especially in theoretical computer science, eg, as a way of representing numbers on the tape of a Turing machine.
In contrast to value systems such as the decimal or binary system it is not possible in Unärsystem to represent by placing a comma non- integers.