HP 25C

Hewlet-Packard
1976

Scientific Calculator
Programmable
Continuous Memory

"The HP-25C was introduced with the HP-67A and the HP-97A on the first of July 1976...Apart from one significant difference it was exactly the same as its predecessor, the HP-25A. Even its codename "Squish" and its $200 price were similar to the codename "Squash" and the $195 price of the HP25A...If the codename Squash suggested that a lot of features had been squashed into such a small package then the name Squish correctly implied that yet another feature had been squeezed in. This feature - the significant difference - was that the HP-25C was the first calculator with "Continuous Memory", as denoted by the letter C after its model number." Wlodek Mier-Jedrzejowicz.
Source: MoHPC - The Museum of HP Calculators

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