If you are an engineer, it is expected that you might have heard about Computer Aided Design ( CAD ). CAD brought a revolution to the mechanical industry. Nowadays no industry can survive without using CAD. Not only mechanical but CAD spread across many other industries. But many of you might not have a fair idea about how CAD evolved over the years. In this article, we try to explore the history of CAD and the evolution of CAD software over the years.