Today in 1956, the development of the Semi-Automatic Ground Environment (SAGE), is disclosed to the public. “Looking back at the development of the computers supporting the SAGE, the origins of many key computer innovations are readily apparent. SAGE’s use of telephone lines to communicate from computer to computer and computer to radar laid the groundwork for modern-day modems… Bob Everett’s invention of the light gun is often referred to as one of the precursor’s to today’s computer mouse. Whirlwind‘s control program, the largest real-time computer program written at that time, spawned a new profession, software development engineers and programmers.

Many other computer breakthroughs such as magnetic-core storage, modular design, interactive graphic displays, on-line common databases, and continuous and reliable operation can also be traced to the development of Whirlwind. In addition, software innovations like the ability to accommodate multiple, simultaneous users, the use of advanced data system structures, structured program modules, and global data definitions grew out of SAGE’s development.”