ISO 80000-1 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, and the International System of Units, SI. The principles specified in ISO 80000-1 are intended for general use within the various fields of science and technology, and as an introduction to other parts of this International Standard. Ordinal quantities and nominal properties are outside the scope of ISO 80000-1:2009. A Technical Corrigendum 1 was published additionally to ISO 80000-1:2009 in 2011. The text of ISO 80000-1:2009+Cor. 1:2011 has been prepared by Technical Committee ISO/TC 12 "Quantities and units" (secretariat: SIS, Sweden) of the International Organization for Standardization (ISO) and has been adopted as EN ISO 80000-1:2013 by the CEN Technical Board (BT). The responsible German body involved in its preparation was Working Committee NA 152-01-01-01 AK "Physikalische Größen" ("Physical quantities") in the Fundamental Technical Standards Committee (NATG) at DIN.