Thoughts on "Sketchpad"

Sketchpad was a system created in the early 1960's by Ivan Sutherland. The system was one of the first Graphic User Interfaces (GUI). It allowed users to make drawings, as opposed to just seeing letters or straight lines on the computer screen. Additionally, through the use of a "light pen," users could actually draw directly onto the computer screen, transposing their drawings into the computer document.

This system seems like an early precursor to Ken Perlin's PAD system that we learned about in class. The similarities are striking, perhaps most notably in the idea of being able to zoom in so many levels (2000 for Sketchpad, and an infinite amount of PAD), and create "sub-documents" within each document.