Capacitors in general are used for many purposes. The two most common are. 1). As a DC block
2). As an AC coupling device. The basic unit is a Farad but this a very large value and we
normally use much smaller values,ie. mF.. Which is = to 0.000001 Farads. Or nF Which is even
smaller and = to 0.000000001 Farads. and lastly pF which is = to 0.000000000001 Farads.
The values are mF,or µF (micro Farad), nF (nano Farad) and pF (pico Farad)
[mF can also be 1E-6 Farads. nF can be 1E-9 Farads and pF is 1E-12 in "scientific"form]
Also with capacitors we have to take into account the working Voltage of the device,this is not
so relevant with resistors. A capacitor is basically two plates of a conducting material separated
by something called a dielectric,(an insulator),it can be air or plastic or paper,in fact lots of things are
used to separate the plates. The larger the plates the larger the value of the capacitor. The greater
the distance between the plates the smaller the value will be. Lets continue on the next page.

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