50g

The HP-35 was HP's first pocket calculator. It was introduced at a time when most calculators (including expensive desktop models) had only the four basic functions. The HP-35 was the first pocket calculator with transcendental functions and the first with RPN.

The early versions said only "Hewlett Packard" on the faceplate and inside HP the product was simply called "The Calculator". Bill Hewlett suggested naming it the HP-35 because it had 35 keys. Later as HP developed more models, "35" was added to the faceplate. The HP-35 and probably the entire HP pocket calculator product line was the sole result of a visionary CEO who chose to ignore the market studies and produce what he felt that engineers would want. His view of the market was that if the engineer at the next bench liked it and thought it would make his job easier, then it was worth doing. The HP-35 was developed in two years, at a cost of approximately one million dollars with twenty engineers. At the time, three to five years was a typical HP development cycle.