Common formulas:

I hope I got all the important ones.
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Units of capacitance: 

It's claimed that the first unit of capacitance was called a "jar", equal to about one nF.  By coincidence, the capacitance of the first Leyden jars was about one nF. 

The present unit of capacitance is the farad (F), named after Michael Faraday.  The farad is an SI unit.  By definition, one F = one coulomb/one volt, where a coulomb (C) = 6.2415 x 1018 electrons.  In other words, if one plate of a capacitor was at ground and the other had one coulomb of electrons on it, the voltage between the two plates would be one volt. 

One coulomb is a lot of electrons.  Given a wire passing one ampere of current, one coulomb of electrons would pass through the wire in one second.  One farad is also a lot of capacitance, so the uF (microfarad, 10-6 farad) and the pF (picofarad, 10-12 farad) are the most common units used.  The nF (nanofarad, 10-9 farad) and fF (femtofarad, 10-15 farad) are also common.