If you get confused when you hear the terms baryes, biots, debyes, dynes, ergs, franklins, and galileos, you're not alone, I do too. If you know that these are units of pressure, electric current, electric dipole moment, force, work, electric charge, and acceleration, well done, you know your CGS units.
It's amazing how dependent I am on the MKS system of units. Coulombs, Newtons, Amps, and Joules have become as second nature to me in physics as miles, pounds, and gallons are in everyday life. So recently, when I was trying to get the charge of an electron in terms of the CGS electrostatic unit (esu), I became curious as to the origins of the systems. I took a look around and found a couple of sites that talk about it.
CGS and MKS Units
Wikipedia
I guess it all started towards the end of the 19th century. The CGS system was introduced formally by the British Association for the Advancement of Science in 1874. The MKS system was created by the Internation Bureau of Weights and Measures in 1889. Not surprisingly, physicists and engineers that worked on smaller scales took to the CGS system whereas those working in larger scales tended towards MKS. Two systems of units contradicted the ideal of a universal measuring system and in 1954, the Tenth General Conference on Weights and Measures adopted units of measure for all international weights and measures, mostly from the MKS system. In 1960, The Eleventh General Conference adopted the name International System of Units (SI) for these units of measure.
Of course it takes decades to centuries for a system of units to officially disappear, and there is alway a niche or two where they hang on.
And what about Imperial Units!?
