Fraps is a program used to capture the screen, with video or just a single picture. You can even get the frames for every 3D application and show them on the screen for everyone of your games or software which takes advantage from 3D acceleration.
There is a known problem for all DirectX games, which won't let you take a screenshot using your keyboard 'Print Screen' key. This is because the program needs some special coding, which Fraps has in its program bundled and you can take screenshots for every single application you might even think of and save them to your desired folder.
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