Windows can make your basement more visually pleasing and improve safety. Large basement windows, sometimes called "egress windows," from Pella of Beltsville are made to permit more light into underground rooms than the older, smaller, rectangular windows that are added above ground. They also give you a way to get out in case of an emergency.
The primary differentiator between basement, or egress, windows and standard windows is that basement windows are required to be big enough for an average-sized person to escape through in order to meet safety requirements set up in building codes. You are able to select from properly sized casement, sliding or double-hung windows when you put in basement windows. Make sure you totally understand local building codes prior to purchasing basement windows.