You may not have any units. Standard units are not used in data on household size, for example.
kg
There are several, collectively known as the SI units.
International System of Units (SI)
SI is short (in French) for International System; the international system of units, used all over the World.
si units are based on the metric system system international (French) international system (English)
SI units describes the metric system units that are used in scientific data.
SI units describes the metric system units that are used in scientific data.
SI units describes the metric system units that are used in scientific data.
SI units describes the metric system units that are used in scientific data.
The SI unit is the standard system of measurement used to help scientist to compare data and communicate with each other about with their results.
Si or international system
Base units
they are units for scientist
The reason is probably a practical one. Many scientist like to compare data internationally and many SI units are relatively practical, and, they are used all around the world. In this way, although in everyday life US Americans use their own measures, in scientific life they use SI units. In this way the scientific community can compare data all around the world.
Watts
the Meter
There are different units for measuring different attributes.