A few of the OS before DOS.

Came out in 1956Created by Robert L. Patrick and Owen Mock

Made for the IBM 701Main Function:

automatically execute a new program once the one that was being executed had finished

GM-NAA I/O

Came out in 1957Stands for Bell Operating SystemWas made by Bell Labs to suite their own needs

Main Function:It was used to efficiently deal with a large number of dynamically loaded short jobs using punched cards.

BESYS

Created in 1958Stands for University of Michigan Executive System

developed at the University of Michigan

Main Function:to make it work better for the small student jobs that were expected to be the primary work load at the University

UMES

Created in 1962Stands for General Comprehensive Operating System

was developed by General ElectricThe operating system is still used today in its most recent version (GCOS 8)

Main Function:GCOS is a multithreading, multiprogramming operating system originally oriented towards batch processing

GCOS

Created in 1964officially known as IBM System/360 Operating System

among the earliest operating systems to make direct access storage devices a prerequisite for their operation

Main Function:It is a group of batch processing operating systems developed by IBM for their then-new System/360 mainframe computer

OS/360

Timesharing / Total Operating SystemCreated in 1964Created by Digital Equipment Corporation (DEC)

Main Function:It supported shared memory and allowed the development of one of the first true multiplayer computer games.

TOPS-10

Created in 1965Stands for Tape Operating System/360

Made by IBMMain Function:

It was used to support the IBM 360 model 30 and similar platforms.

TOS/360

http://en.wikipedia.org/wiki/Timeline_of_operating_systems http://en.wikipedia.org/wiki/University_of_Michigan_Executive_System http://en.wikipedia.org/wiki/University_of_Michigan_Executive_System http://en.wikipedia.org/wiki/GM-NAA_I/O http://images.e800.com.cn/articles/

2009/4/15/12397807225872009041515311248420.jpg http://wallpaper-s.org/30__Computer_Club_IBM_Keyboard.htm http://wallpaper-s.org/30__Computer_Club_IBM_Keyboard.htm http://thewallpaperhunter.com/places/structures/images/a-century-old-

university-of-michigan-l.jpg http://en.wikipedia.org/wiki/General_Comprehensive_Operating_System http://www.feb-patrimoine.com/photos/dps7_80.gif http://en.wikipedia.org/wiki/OS/360 http://en.wikipedia.org/wiki/TOS/360 http://www.maximumpc.com/files/u22694/Bios-Opener-415.jpg http://history.nih.gov/museum/practitioners/RTPP/data/DECsystem-2020-

crew.jpg http://ed-thelen.org/comp-hist/vs-ibm-360-30.jpg

Sources…