Visible Storage - samples from the collection
Exhibit Search
Overview Ancient-1940s 1940s-1960s 1960s-1980s 1970s-1990s Exhibit Floorplan Back to Previous Page

HP 35

Bowmar Brain

Click to see bigger picture

Early HP-35 adverstisement, c. 1972
Credit: Hewlett-Packard Company Archives


All desktop calculators prior to the 1960s were mechanical. By the mid-twentieth century most had keyboards and were powered either by the depression of keys or with a crank. The invention of the integrated circuit in 1971 fostered the electronic calculator revolution. By 1974, an electronic calculator costing less than $50 was more powerful than its mechanical equivalent costing $1,500 or more. As a result, manual slide rules, favored by scientists and engineers, quickly became obsolete. Today many electronic calculators are small, sophisticated programmable computers with more power than the mainframes of 40 years ago.

View on Plan
Computer History Museum
feedback credits