Desktops and Notebooks: How the HP-35 Calculator Killed the Slide Rule and Made an IT Giant
In the early 1970s, the slide rule was standard equipment for students, engineers and scientists. The personal computer was still a twinkle in the eyes of the visionaries. Then, in 1972, Hewlett-Packard introduced the world's first scientific pocket calculatorthe HP-35and delivered portable "computing power" into the hands of users. An instant hit among scientists and engineers, the HP-35 soon displaced slide rules and marked the birthplace of HP's innovative and highly successful heritage in the handheld calculator market. On the next several pages are some of the major innovations in the portable calculator world that were contributed by HP. It all started on a direct request from William Hewlett himself, with the only qualification being that "it fits in my shirt pocket." Dave Cochran, the original HP-35 product manager, said on April 14 that he sometimes wanted to tell Mr. Hewlett's tailor "to enlarge his pockets and not tell him."