Decimal number system

The decimal number system is a positional numeral system with base 10. Each digit in a number has a value determined by its position, which is a power of 10. Any whole number can be written as a sum of digits multiplied by powers of 10. For example, $N = d_n \times 10^n + d_{n-1} \times 10^{n-1} + \dots + d_1 \times 10^1 + d_0 \times 10^0$, where each $d_i$ is a digit from 0 to 9.

Important properties

• Base 10: Each place value is a power of 10.

• Digits: Only the digits 0–9 are used.

• Positional: The value of a digit depends on its position.

• Decimal point: Used to represent fractions (decimal numbers).