International System of Units SI
Units of Measurements SI

In chronological order, the stages in the development of the international system of units were as follows.

In 1948, the 9th General Conference on Weights and Measures instructed the CIPM, in Resolution 6, to open an official inquiry into the opinions of scientific, technical and educational circles in all countries, to centralize the responses and to issue recommendations concerning the establishment of a practical system of units of measurement, capable of being adopted in all countries signatory to the International Metre Convention (§