"The talk Whirlwind Software Restoration provides an overview of the Whirlwind real-time digital computer designed at MIT. When brought on line in 1950, Whirlwind was one of the largest computers in existence. We then focus on restoration of one application of Whirlwind, development and demonstration of an interactive real-time air defense application, using radar data to compute headings to guide piloted interceptor aircraft towards intruders. The 1951 demonstration ultimately evolved into the SAGE continental air defense system."