"Clark next led hardware design for the TX-2 with a focus on graphical interactivity. MIT doctoral student Ivan Sutherland realized that Clark's system enabled

"Clark next led hardware design for the TX-2 with a focus on graphical interactivity. MIT doctoral student Ivan Sutherland realized that Clark's system enabled human-computer interaction concepts dreamed of 20 years prior by another MIT-trained engineering legend, Vannevar Bush. Sutherland used TX-2's light pen and screen to develop a graphical design application called Sketchpad." Both the genesis of the GUI and object-oriented programming took place right there.