Capacitor Tutorial by Tony van Roon
Capacitors are funny things, creating enormous problems when troubleshooting for a fault and yet are absolutely necessary for almost every electronic circuit. They come in a variety of sizes, shapes, models, or if you so desire they can be manufactured by your specifications.
They also come in a variety of materials, to name a few: Aluminum foil, Polypropylene, Polyester (Mylar), Polystyrene, Polycarbonate, Kraft Paper, Mica, Teflon, Epoxy, Oil-filled, and the list goes on. The value of a capacitor can vary from a fraction of a pico-Farad to more than a million µFarad (µ means 'micro'). Voltage levels can range from a couple to a substantial couple hundred thousand volts. The largest capacitor in my own collection is 680000 µF at 10Volts. A big sucker measuring about 10 x 4 inches! Does it still work? You bet! It will still zap the soles of your shoes... I use it on occasion to recondition shorted NiCad batteries which I use for my Radio Control gear.
But the hobbyist like you and me only use a couple types like the common electrolytic, ceramic, and tantalum's.
Look below for a more detailed explanation.
Electrolytic - Made of electrolythe. Most common type capacitor. Applications: Filters, Timing circuits. Pro's: Cheap, readily available, reliable, Con's: Not very accurate, drifting.
Tantalum - Made of tantalum, drop-shaped Pro's: Small size fits anywhere, cheap, reliable, availability Con's: Easily damaged by spikes
Ceramic - Made of ceramic, plate-shaped Pro's: Comes in very small size and value, very cheap, reliable Con's: Subject to temperature drift