|Numeral systems by culture|
|East Asian numerals|
|List of numeral system topics|
|Positional systems by base|
|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.
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.
Today, mainly bases 2, 8, 10, 12 and 16 are in use.
Other websites [change]
- History of Counting and Numeral Systems-PlainMath.Net
- Number Sense & Numeration Lessons
- Counting Systems of Papua New Guinea