I have wondered this on and off for years, and was prompted to find out the answer:

Any time I've seen capacitors, they're listed with milli- or pico-Farad ratings. I understand that, nowadays, we have special purpose supercapacitors that package "whole" Farads into single components.

But, why on earth did "they" use such a large base value that for "most" applications you'd need something in the milli- to pico- range? It just seems ... unnecessarily skewed.

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    \$\begingroup\$ Like most modern units, farad is defined based on SI base units. It's 1F = 1 As/V. That's it. Nothing to answer here. \$\endgroup\$ – Marcus Müller Jan 2 '20 at 12:57
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    \$\begingroup\$ Duplicate of Why is the unit for capacitance so large? \$\endgroup\$ – Tom Carpenter Jan 2 '20 at 13:00
  • \$\begingroup\$ Same question could be posed regarding mass, which is already 'compensated' by the standard prefix kilo... \$\endgroup\$ – Huisman Jan 2 '20 at 13:02
  • \$\begingroup\$ @Huisman but that's a base unit, and thus so defined. You'll notice that, for example, J is well definable with respect to kg without any further prefixes. Nice, isn't it? \$\endgroup\$ – Marcus Müller Jan 2 '20 at 13:52
  • \$\begingroup\$ because it's based on 1 second. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jan 2 '20 at 13:59

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