Millennium, which would become Windows Millennium Edition (or Windows ME), remains one of the most controversial operating systems to date. Some of its downsides are frequently cited in criticisms like no real mode DOS support and almost completely ditching VxDs in favor of the then shaky WDM standard. At the same time, Windows ME's various quality of life improvements over 98 like USB mass storage device support, a leaner Explorer toolbar, and faster hardware detection dialogs often get overlooked.
Unlike Windows 95 and 98 which were widely used in both households and enterprise environments, this installment in the 9x family was specifically home-oriented. With this came several new software components useful for that market, including a heavily spiced up media player, a basic video editor, and several new games - things that its direct successor tends to get more credit for.
Still, Millennium takes a number of strange U-turns resulting from its desire to have a "diet DOS" kernel. Internally, the startup and shutdown routines are very different, real mode DOS drivers cannot be used at all, and, of course, DOS programs can only be run in protected mode windows. They do a pretty good job at it, but a lack of real mode support outside of an emergency boot disk is significantly limiting for those wanting to run legacy software exactly how they want to. On the plus side, this does mean a number of notorious bugs like con\con have no effect in Windows ME.
This version of Windows has not yet been fully covered on this website, so more build pages will be added or updated whenever any of us get around to them. Thanks for dropping by!