Alan Kay can be credited in the late '60s with the visionary prototype of a
small, powerful computer, or one of the first usable laptops. "I...started thinking about what would it be like for millions of people to have one of these machines," he later wrote. The technology to build his idea did not yet exist, so
he concentrated on other things such as software design and the creation of easy-to-use programs, which led to such advances as graphical interfaces. But his notebook computer prototype was the inspiration later used by Apple and others.