Sketchpad

Sketchpad, created by Ivan Sutherland in 1963, is an early computer graphics program that allowed users to draw on a computer screen using a light pen. It is considered one of the first graphical user interfaces and a pioneering work in the field of interactive computer graphics. Sketchpad introduced concepts such as object manipulation, constraint satisfaction, and layers, which have influenced modern computer-aided design (CAD) software and graphical applications.