The symbol used to point to some element on screen. On Windows, Mac and other graphics-based screens, it is also called a "pointer," and it changes shape as it is moved with the mouse into different areas of the application. For example, it may turn into an I-beam for editing text, an arrow for selecting menus or a pen for drawing.
On DOS and Unix command lines as well as other character-based screens, the cursor may be a rectangle, an underline or a vertical line, and it is typically blinking. See database cursor
A pen-like or puck-like device used with a digitizer tablet. Officially called the "tablet cursor," as it is moved across the tablet, the screen cursor moves correspondingly. See digitizer tablet