Alcance
This document gives general information and definitions concerning quantities, systems of quantities, units, quantity and unit symbols, and coherent unit systems, especially the International System of Quantities (ISQ).The principles laid down in this document are intended for general use within the various fields of science and technology, and as an introduction to other parts of this International Standard.The ISO/IEC 80000 series does not, as yet, cover ordinal quantities and nominal properties.