1958: ''How the Web Was Won''

 

The Semi-Automatic Ground Environment (SAGE)  air defense system was designed by IBM for the US Air Force in the early 1950s to coordinate the response to air attack:

''Its innovative technological contributions to IBM and the IT industry as a whole were significant. These included magnetic-core memories, which worked faster and held more data than earlier technologies; a real-time operating system (a first); highly disciplined programming methods; overlapping computing and I/O operations; real-time transmission of data over telephone lines; use of interactive terminals and input light pens (a first); redundancy and backup methods and components; and the highest reliability of computer systems (uptime) of the day. It was the first geographically distributed, online, real-time application of digital computers in the world. Because many of the technological innovations spun off from this project were ported over to new IBM computers in the second half of the 1950s by the same engineers who had worked on SAGE, the company was quickly able to build on lessons learned in how to design, manufacture and maintain complex systems.''
http://www-03.ibm.com/ibm/history/ibm100/us/en/icons/sage/

SAGE Air Defense System general manual (I.B.M.,1958)

https://archive.org/details/bitsavers_ibmsageSAGm1958_18586730

SAGE Air Defense System Input System (I.B.M.,1958)

https://archive.org/details/bitsavers_ibmsage352_26517675