What they are and what they are made for

An Angle grinder is a tool that is used for cutting, grinding and other coarse work.

It is usually electric, and uses exchangable grinding dishes. These dishes can be of stone, metal, sand-covered metal, or even diamond-coated materials.

d b
d¨ ,-~^^^~-. ¨b
__________ __.-' d b .
d . . . ¨¨¨¨¨¨¨¨ d b
____,d¨ . . . . . . . m m
=======____. . . . . . . . m () m
"q . . . . . . . q p
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on/off trigger -> | | w _____ w <-- Grinding plate
Okay.. You may stop laughing at my ASCII art now. Anyway.. It should give a pretty good impression of what it looks like.

Angle grinders are usually two handed. One hand goes on the trigger and the handle (like you'd hold a drill) and the other one goes on another handle that sticks out on the opposite site of the grinding plate (in the drawing, it would stick out on the opposite site of the little ( ) thing in the middle of the grinding plate.

Angle Grinders in Show Use™ :)

For some reason, the Norwegian extreme-entertainment genre (of which I used to be a part) has taken to using angle grinders instead of chain saws, because angle grinders are safer, and they make lots of dramatic sparks.

To use angle grinders in shows, find a hard, coarse grinding dish. Then you need some hard metal that makes nice, big sparks. Myself, I've found that old umbraco tools etc. (basically all stainless steel) are of great use for this, because they are fairly hard and make nice sparks.

Making sure to protect your eyes, have a friend use the angle grinder to shoot loads and loads of sparks at you. They might hurt and burn into your skin, but if you are on stage, and you have enough adrenaline and endorphines running through your body, you won't notice (just make sure to remove the steel splinters from your hands). The sparks will light up the stage (provided, of course, that it was dark in the first place), and the red-hot steel splinters flying into your hands will bounce off, looking really cool.