Windows 1. 1985: Multitasking,
windows. Close/minimize/maximize buttons.
Windows 2 1988. re-sizable, movable windows.
Windows XP 2001: Pretty blue windows.
Windows Vista 2007: Transparent windows, flip-3d.
Window 8 metro 2012: No separate windows or any form of multitasking, no close button, no resizing. Can only do one thing at a time.