Despite these breakthroughs, the industry had still not developed a practical means to input graphics, or any sort of graphical communication system for designing with computers. Then, in 1960, Ivan Sutherland used the TX-2 computer produced at MIT's Lincoln Laboratory to produce a system known as ``Sketchpad'', which is considered to be the first step towards the creation of the CAD industry \cite[1]{bozdoc}.


This system was designed to be a ``man-machine graphical communication system'' that eliminates cumbersome input methods, such as manually typing coordinates and commands \cite[501]{sutherland}. Instead of a complex, typed syntax, an intuitive ``light pen'' allows a user to interact immediately with Sketchpad by touching the pen to a monitor. Ronald Baecker recently wrote an article on human-computer interaction, and discusses the influential role that Sketchpad system had in the 1960's: ``Sketchpad demonstrated the potential for effective computer-aided sketching and design through innovative concepts'' \cite[23]{baecker}. This potential inspired many other pioneering ideas within interactive computer graphics, and provided a working prototype for CAD applications.


\begin{interactive}
\img{/app/assets/paper/sutherland.jpg}

Ivan Sutherland using the TX-2 computer to demonstrate ``Sketchpad''
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\includegraphics{images/sutherland.ps} \\
\addcontentsline{lof}{figure}{Ivan Sutherland using the TX-2 computer to demonstrate ``Sketchpad''.} 
Ivan Sutherland using the TX-2 computer to demonstrate ``Sketchpad''. \\
(source: http://design.osu.edu/carlson/history/images/ivan-sutherland.jpg)
\end{center}
\end{print}





Human Computer Interaction