The International System of Units, known by the international abbreviation SI[a] in all languages: 125 : iii and sometimes pleonastically as the SI system,[b] is the modern form: 117 of the metric system[g] and the world's most widely used system of measurement.: 123 Established and maintained by the General Conference on Weights and Measures[j] (CGPM[k]), it is the only system of measurement with an official status[m] in nearly every country in the world,[n] The SI comprises a coherent[...