Take a screen shot in Windows by pressing the Print Screen button on your keyboard (or Alt+Print Screen, to capture an active window instead of the entire desktop). This saves the screen shot to the clipboard, enabling you to copy and paste it into an image editor.
Pressing the Print Screen button may create a screen shot of the desktop, but this act in itself does not save the image to the hard drive. Instead, it creates a file that is temporarily stored in the computer's clipboard. To permanently save a screen shot, open up an image editor, such as Microsoft Paint or Gimp, and paste the image by pressing CTRL+V. Go to the menu bar, and select File, then Save As to save the screen shot as a GIF, PNG or JPG file.