Ivan Sutherland's PhD thesis in 1963 resulted in the creation of Sketchpad, a pioneering computer application. Sketchpad was a pioneer in the field of human-computer interaction (HCI). Sketchpad is regarded as the forerunner of today's computer-aided design (CAD) software. It is also recognised as an important step forward in the development of computer graphics. Sketchpad, for example, was used to develop cutting-edge object-oriented programming and the graphical user interface (GUI).
Sketchpad is explained by Techopedia.
Ivan Sutherland demonstrated with Sketchpad that computer graphics may be used for both technical and artistic applications in addition to being an innovative technique of HCI. It could handle restrictions; for example, drawing a constrained ellipse resulted in a circle. Sketchpad also has certain CAD functions, such as the ability to calculate loads on beams.
Sketchpad allowed users to draw on a computer screen with a light pen. It offered the "ring" list framework and used value inference to solve constraints. The drawings created with Sketchpad were saved in the computer's custom constructed ring structure. This ring structure included instant topological information processing, which eliminated the need for any searching.
Drawing was used as the computer's unique interaction medium in Sketchpad. The system had input, output, and computation routines that enabled it to decode data drawn directly on a computer screen. Drawing scientific, mechanical, mathematical, electrical, and animated designs was a breeze with Sketchpad.
Sketchpad extension was a one-of-a-kind technology that aided in the understanding of processes such as the concept of links, which could be conveyed visually. It was easier to design highly accurate and repetitive drawings with Sketchpad. It also included the ability to alter an image that had already been drawn.