1
Press the "Print Screen" (⎙ PrtScr) key on your keyboard. This will capture an image of your entire screen and copy it to the clipboard. The dimensions of the image will be the same as your desktop resolution.
The ⎙ PrtScr button may be labeled "PrtScn", "Prnt Scrn", "Print Scr", or something similar. On most keyboards, the button is usually found between F12 and Scroll ⇩. On laptop keyboards, you may have to press the Fn or "Function" key to access "Print Screen". [1]
You will not receive any confirmation that the screenshot has been taken.
http://www.wikihow.com/Take-a-Screenshot-in-Microsoft-Windows