I could use some help with a DDC number for Microsoft Windows.  Is it a user interface or an operating system?

When Microsoft Windows first appeared, it was a user interface that ran on top of the operating system DOS.  Then Microsoft Windows became an operating system itself, and the operating system DOS went out of use except on old computers.  No recent or current version of Microsoft Windows should be classed as a user interface.

Works about operating systems--works that focus on the operating system itself and how to use it--are classed in 005.44.  For example, works about Windows 95, Windows 98, Windows 2000, and Windows XP are all classed in 005.446, a built number that means operating systems for microcomputers.  The DDC 21 number was 005.4469, but the 9 for "Specific programs" has been discontinued in DDC 22. 

General works about application programs that run on a particular operating system are classed in 005.3682.  There are many kinds of application programs, e.g., computer games, tax preparation programs, word processing programs; only comprehensive works on many kinds of application software are classed in 005.3682.  Works that focus on the operating system itself, instead of the application software that runs on it, do not belong in 005.3682; they belong in 005.446.

Submitted by: Thanks to Elizabeth Erlich, Macomb County Library, Michigan, for submitting this question.
Last revised: 03 June 2004