Why is the metric (SI) system called a decimal system of measurement

The metric system is the oldest name for the international system of units. SI unit or the international systems of units are based on seven basic units; the meter, kilogram, second, ampere, Kelvin, candela and mole. All of these basic units are divided into multiples by a power of ten. For example in meters, 1 meter is equal to: 1000 millimeter, 100 centimeter, 10 decimeter, 0.1 decameter, 0.01 hectometer, 0.001 kilometer and so on and so forth.