International System of Units

What Does International System of Units Mean?

The International System of Units (SI) is considered the modern form of the metric system and is now the most widely used system of measurement in the world. It is used both in science and in everyday commerce. The standard was based on the meter-kilogram-second (MKS) system and was published in 1960 as a result of the initiative that started in 1948. It is part of the International System of Quantities.


Techopedia Explains International System of Units

The International System of Units consists of coherent systems of measurement built around 7 base units, 22 named and a number of unnamed coherent derived units, and a set of prefixes that serve as decimal-based multipliers.

It is declared as an evolving system, so there can be new units and prefixes created, and even unit definitions can be modified through an international agreement as the technology and precision of measurements improve.

All SI units can be expressed directly or in terms of standard multiples or fractional quantities by powers of 10 ranging from 10-24 to 1024.

The seven base SI units are as follows:

  • Meter
  • Kilogram
  • Second
  • Kelvin
  • Ampere
  • Candela
  • Mole

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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…