Alternatively referred to as base-10 and denary, decimal is a numbering system comprised of the numerals 0 to 9 that was first used by the Chinese in 1350 B.C.
Decimal numbers can be placed in a decimal place value chart to represent a value. For example, you could use the following decimal chart to get the number 593.
In the above chart there are "5" one hundreds (500), "9" tens (90), and "3" ones to get the decimal number 593.
A decimal fraction is a fraction with a denominator of a power of ten, determined by the number of digits to the right of the decimal point or decimal separator. For example, 2/10, 2/100, and 2/1000 are expressed in decimal as 0.2, 0.02, and 0.002. Decimal fractions can be used in a calculator or spreadsheet to calculate values.