Engineering

DOS

* DOS short for Disk Operating System, is an acronym for several closely related operating systems that dominated the IBM PC compatible market between 1981 and 1995, or until about 2000 including the partially DOS-based Microsoft Windows versions 95, 98, and Millennium Edition.

* DOS is a single-user, single-tasking operating system with basic kernel functions that are non-reentrant. The DOS kernel provides various functions for programs (an application program interface), like character I/O, file management, memory management, program loading and termination.

* Re-entrant - it cannot be interrupted in the middle of its execution and then safely called again ("re-entered") before its previous invocations complete execution. only one program at a time can use them and DOS itself has no functionality to allow more than one program to execute at a time.

Windows 92

* Windows 3.1x (codenamed Janus) is a series of 16-bit operating systems, produced by Microsoft for use on personal computers.

* versions were released between 1992 and 1994 until the series was superseded by Windows 95

* Windows 3.1 was originally released on April 6, 1992;

* official support for the Windows 3.1 family ended on January 1, 2002,

* licensing for Windows for Workgroups 3.11 on embedded systems continued to be available until November 1, 2008.

* can theoretically access up to 4GB of RAM, although it is limited to 64MB because of the way it detects the amount of RAM installed in the computer.

* The File Manager was significantly improved over Windows 3.0. Most significantly, Windows 3.1 added multimedia support .

* On August 11, 1993, Microsoft released an update for Windows 3.1 known as Windows 3.11. Thus, Windows 3.11 is not a stand alone version of Windows, but rather a software update from Windows 3.1, much like modern Windows service packs.

* On November 22, 1993, Microsoft released a Simplified Chinese version of Windows for the...