Tally Marks

The unary system based on successive marks consists of recording each addition of n units by n marks (generally lines, bars or sticks). The system uses a single symbol (the system is said to be unary) and allows the count to be updated (for numbers up to a few tens, beyond that, the system is neither practical nor efficient).

The use of tally marks is to group each set of 5 to facilitate counting

Example: 8 is written (notation used in France or South America)

Several graphic variants are possible as the square

Example: 8 is also written as (notation used in Europe, North America or Oceania)

The unary counting system by marks is often used for a count of days remaining, a calculation of scores, number of points of a match, etc.

Reading consists of counting the number of marks (of lines) in order to deduce the value.

Example: for the value 14 (there are 14 marks in total)

Usually marks / lines / sticks are written in lines or in groups. The symbols are generally all the same and simple (bars or dots).