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Measurement impacts everyone around the globe, which is why the scientific community comes together each May to celebrate the standardization of measurement on World Metrology Day.
Time of day, miles per gallon, temperature, etc. — all of these items can be measured, but it was not until May 20, 1875, that multiple countries gathered at the first Metre Convention in Paris, France to establish standards of measurement.
During the first convention, the 17 participating countries were only concerned about standardizing mass and length. However, over the years, participation in the conventions grew, as did the number of standardized measurement units.
There are now seven basic units of measurement agreed upon internationally — length, time, amount of substance, electric current, temperature, luminous intensity, and mass.