How to print what you see on your screen.
First, find the Print Screen key on your keyboard, which might be labeled PrtScn.
To capture the entire screen (everything you see on the screen, including all open windows), press the PrtScn button. This screenshot will be placed in your clipboard.
Alternatively, to capture just the active or foremost window, press Alt+PrtScn. Now you can paste the image into an email or document, or open an image editing program like Microsoft Paint and either go to the Edit menu then select Paste, or press Ctrl+V to paste the image into the program. Now you can manipulate the image.
Windows Vista and Windows 7 come with another screen capturing tool, the Snipping Tool. With the Snipping Tool, you can define areas of the screen to capture (an irregular shape, rectangle that you draw, selected window, or the entire screen), annotate the screen capture. Since you can save the image directly from the program, the Snipping Tool also saves you the step of having to open Paint or a different program and pasting the image from the clipboard.
To use the Snipping Tool: Full size - Click Start, then All Programs, then Accessories, and then Snipping Tool. Click the down arrow next to the New button to select your snipping type. Then use your mouse to select the area of your screen or window you want to capture. Click and go.