Numeral system

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Numeral systems by culture
Hindu–Arabic numerals
Western Arabic
Eastern Arabic
Khmer
Indian family
Brahmi
Thai
East Asian numerals
Chinese
Suzhou
Counting rods
Japanese
Korean 
Alphabetic numerals
Abjad
Armenian
Cyrillic
Ge'ez
Hebrew
Greek (Ionian)
Āryabhaṭa
 
Other systems
Attic
Babylonian
Egyptian
Etruscan
Mayan
Roman
Urnfield
List of numeral system topics
Positional systems by base
Decimal (10)
2, 4, 8, 16, 32, 64
1, 3, 9, 12, 20, 24, 30, 36, 60, more…

A numeral system (or system of numeration) is a way to write numbers. Roman numerals and tally marks are examples. "11" usually means eleven, but if the numeral system is binary, then "11" means three.

A numeral is a symbol or group of symbols, or a word in a natural language that represents a number. Numerals differ from numbers just as the word "rock" differs from a real rock. The symbols "11", "eleven" and "XI" are different numerals, all representing the same number. This article tries to explain the different systems of numerals. See also number names.

Bases[change | change source]

There are different symbols that can be used to make numbers. In a system with base 10 (the normal decimal system), usually the symbols 0,1,2, 3, 4, 5,6, 7, 8, and 9 are used. The numbers 0 to 9 can be written as one symbol, 0 ... 9. To count past 9, symbols have to be put together. 10 can be seen as 1 in the tens' place and 0 in the ones' place, or as 1 times 101 plus 0 times 100. With a base of 2, only the symbols 0 and 1 are used. 10 in base 2 notation is therefore 1 times 21 plus 0 times 20. This is the same as 2, in the base 10 notation.

For bases bigger than 10, capital letters are used as symbols. For example, the hexadecimal numeral system (base 16) uses the numerical digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F.

Today, mainly bases 2, 8, 10, 12 and 16 are in use.

Most electronic calculations are done in binary (base 2), but most people do calculations in decimal (base ten).

Other websites[change | change source]

English Wiktionary
The English Wiktionary has a dictionary definition (meanings of a word) for: numeration