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Windows is the popular operating system by Microsoft for PC-AT computers. It is a Graphical User Interface (GUI) designed for multi-tasking. It seems they (and Apple) stole the idea from Xerox. Their prior operating system, DOS (Disk Operating System), was a Command Line Interface (CLI) not designed for multi-tasking. Various add-ons to DOS could allow multi-tasking and/or provide a semi-graphical Text User Interace (TUI) or even a real GUI. In fact, several versions of Windows were add-ons to DOS. Although not discussed further, it should be noted they have tried (with limited success) to expand the scope of Windows to systems other than the PC.


Below is an incomplete list of the various versions of Windows. In particular, I have never seen 1.0 or 2.0, but I have read that they were really bad. No matter how much you might hate Windows today, it use to be much worse!

  • Windows 3.1 (a.k.a, Windows for Workgroups)
  • Winodws NT 3.x
  • Windows '95
  • Windows NT 4
  • Windows '98
  • Windows 2000
  • Windows ME
  • Windows XP
  • Windows 2003
  • Windows Vista
  • Windows 2008
  • Windows 7
  • Windows 8
Windows 3.1 was an add-on for DOS version 6. Windows '95, '98, and (arguably) ME were built on-top of a normally-hidden, special, upgraded version of DOS and are collectively known as Win9x. Windows ME actually reversed the relationship such that (normally) Windows was the primary OS and DOS was a subsystem (but using ME's emergency boot disk, the 'traditional' Windows-on-DOS configuration could be achieved).

The other versions of Windows are all in the NT (New Technology) series.  As far as I can tell, NT 3 and NT 4 were desgined as server/professional operating systems, meant to complement the "consumer" systems (Win 9x). All the NT series are more stable than the ones based on DOS. The "consumer" systems however were generally more user-friendly by offerering useful things such as plug-and-play (hot swap) and DirectX for games. Another distinguishing feature is Win9x used the FAT (file allocation table) file system while the NT series used NTFS (New Technology File System).  One big difference between the file systems is that NTFS allows for sophisticated ownership and permissions to be assigned to files and directories; this is important in a network or multi-user environment which strengthens the argument that the NT series was for servers and 9x was for consumers.

With Windows 2000, Microsoft was able to integrate those nice features which thus seems to have killed the Win 9x line.  It was the first Windows version to natively support both FAT and NTFS. Following that, the professional series seems to be those that retain a year in their name (e.g., Windows 2003 or Windows 2008) while the consumer series have other names like Windows XP, Vista, 7, or 8. Of course this is just my opinion/impression ... you'd have to ask them how they actually come up with their names!

© H2Obsession, 2014

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