Drawing Environment > Ribbon menus > The “View” tab > The “Zoom” panel > Directly visible commands

Zoom Window means that you select the command, pick one point and thereafter an opposite point. The two points then creates a window that is zoomed to cover the entire screen. Before the age of the mouse-wheel, this was maybe the most common and effective way to zoom in.

Please note that the relationship between height and width of the window should be approximately the same as for the screen itself. Otherwise the result of your zooming might be somewhat surprising to you.