Links between the seven SI base unit definitions. Counterclockwise from top: second (time), metre (length), ampere (electric current), kelvin (temperature), candela (luminous intensity), mole (amount of substance) and kilogram (mass).

The International System of Units is the standard modern form of the metric system. The name of this system can be shortened or abbreviated to SI, from the French name Système International d'unités.

The International System of Units is a system of measurement based on 7 base units: the metre (length), kilogram (mass), second (time), ampere (electric current), kelvin (temperature), mole (quantity), and candela (brightness). These base units can be used in combination with each other. This creates SI derived units, which can be used to describe other quantities, such as volume, energy, pressure, and velocity.