A button on screen shaped like a hand that is used to move objects within a window. For example, if the image is larger than the current window size, the grabber hand allows the image to be scrolled within the window. When the button is selected, the screen pointer (cursor) turns into a hand symbol, and when the mouse is clicked over an image, it "grabs" the image so it can be moved.
The Grabber Hand
This tool was widely used on the Macintosh before it found its way into the Windows world.