Decimal

Decimal is the most commonly used system in everyday life. It's a place-value system based on powers of 10, which means that for example the number 365 equals (3 × 102) + (6 × 101) + (5 × 100). 

The system's main advantage is that it allows us to express fractions like 1/5, 1/2 or 1/4 in a convenient form.