"His name and his pioneering work have been mentioned a couple
of times before during this series: Ivan Sutherland's Sketchpad,
"released" in 1963. Regular readers will already know what
Sketchpad was; Sketchpad was a sketching program, running on a
Lincoln TX-2, and it allowed its users to draw various shapes, and
manipulate these shapes. You interacted with the program using a
laser pen and a keyboard with keys mapped to specific actions you
could perform."