PRESENTING THE

HP-35

The Electronic Slide Rule

The world's first scientific pocket calculator. Thirty-five keys. Four-level RPN stack. Born 1972.

0
Example: To calculate 3 + 4: press 3 ENTER 4 +
RPN Logic
Four-level stack. No equals key. Think in postfix.
35 Keys
Trigonometric, logarithmic, and exponential functions at your fingertips.
Since 1972
The device that replaced the slide rule and changed engineering forever.