Today marks the 40th anniversary of the release of the Hewlett-Packard HP-35
calculator, which took place 1 February 1972.
The first handheld scientific calculator, it included trigonometric and logarithmic functions.
Bill Hewlett himself had challenged his engineers to build it small enough so that it could
fit in a shirt pocket.
The story goes, it was designated the HP-35 because it had 35 keys.
It was an instant success and its introduction heralded the end
of the slide rule as the engineer or scientist's personal, portable calculating
device of choice.
Slide rules had reached their design high point just before the HP-35's release
with instruments such as this Faber-Castell Novo-Duplex.
See
http://sliderulemuseum.com/Faber/S12...tell_2-83N.jpg
I still have one somewhere.
To read more about the HP-35's history and development, follow the links on this page here -
http://www.hp.com/hpinfo/abouthp/his...lsystems/0023/
When one considers that we were using plastic slide rules 40 years ago,
it gives reason to pause and wonder what people's personal computing requirements
will be like in another 40 years from now.