Take a screenshot of the entire screen:
Press the Print Screen button on your keyboard. This will copy an image of the screen to the clipboard, making it available to paste into a program such as Word or Paint.
Take a screenshot of just a portion of the screen:
1) Click the Start button and type snipping in the search box:
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2) Select Snipping Tool from the list:
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3) Using your mouse, left-click and drag across the desired area of your screen, and then release:
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4) A window will open displaying your screenshot:
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5) Click one of the buttons on the toolbar to either Save, Copy or Email your screenshot, as seen above.