My friend wanted me to show him how to take a screen cap, and I had nothing else to do so I made this little pictorial.
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Screen CapturesAllright, the first thing you need to do is take the actual picture. To do this, look around on your key board for the "Prtscn," this stands for "Print Screen." It's location differs from keyboard to keyboard, on a desktop keyboard it's usually on the top row. But no matter what, every keyboard has it. Just press the key. Now, where the heck is the shot? What the computer does is put it on your clip board, when ever you copy text, that's where it goes, the same apply to pictures. So make sure not to copy anything else 'till we're all done. Now, the next step is to go to any picture editing software.

Any work, but Paint is the simplest and comes with every version of windows. So open Paint. For those without it on your desktop go to Start>All Programs>Accessories>Paint. Now, we're going to paste the picture into paint. It's very simple, just go to edit, and paste.

Oh look, there's your screen shot! Now, just save the picture with what ever name you want.

And upload it and post it like any other picture. There ya go.