Most people don't know that you can take screenshots just by using the correct keyboard short-cuts.
Here are the two main keyboard short-cuts to take screenshots with:
The screenshots are placed on the Windows Clipboard. Now open any image application or program that supports the Windows clipboard and simply click on the paste button to view the screenshot taken.
So there you have it, just by simply knowing which keyboard short-cuts to make, you can make images of any application or desktop scene.