The HP-35: The most important Reverse Polish Notation calculator in the world [Update]

The beloved HP-35, one of the first scientific calculators able to “perform transcendental functions such as trigonometric, logarithmic and exponential functions” with an LED display just received an IEEE Milestone Award. The award commemorates important steps in computing technology.

Sadly, HP’s current computing technology is sub-par and won’t let us embed a video of Dean Takahashi and some guy named Wozniak talking about the HP-35 in reverent tones.

[youtube http://www.youtube.com/watch?v=jSOfd427bzQ&hl=en&fs=1]

# The HP-35, named for its 35 keys, was the first handheld calculator to perform transcendental functions such as trigonometric, logarithmic and exponential functions.

# At the time, contemporary calculators could only perform four basic functions – addition, subtraction, multiplication and division.

# The now classic “Reverse Polish Notation” (RPN) first used in the HP-35 has become the most efficient way known to computer science for evaluating mathematical expressions.

# In the first three years after its introduction in 1972, sales of the HP-35 Scientific Calculator exceeded 300,000 units.

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# Forbes ASAP named HP 35 as one of the 20 “all time products” that have changed the world.

# It was the world’s first handheld scientific calculator with a LED display.

# HP-35 has traveled to the top of Mt. Everest for use in altitude and navigation calculations.

# HP-35 is regularly used to navigate ships.

# HP-35 has been used by astronauts aboard spacecraft to calculate the exact angle of re-entry into the Earth’s atmosphere.

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