Known features that already exist in Windows 7, and earlier.

Screen captures.
Ever need to capture part of the screen? The Print Screen button will copy the entire contents of your monitor (or monitors) to the clipboard. From there you can paste into Paint, or other picture editing program and save.
If you need to only capture the contents of a window, you press Alt + PrtScrn.
The snipping tool
What if you need to capture only part of a Window? If you have Windows Vista or 7, just click start and search for “snip”.
The snipping tool allows you to drag your cursor around any area of the screen, capture it, annotate it (draw / highlight), and save as png, gif or jpg!