(Originally posted at http://joelnoche.multiply.com/journal/item/94/HP-35s on March 22, 2012 2:41 AM)
When I was a child, I would read 1970s issues of Scientific American that my father bought and I would see advertisements for Hewlett-Packard calculators. They were quite unusual; they used reverse Polish notation and some of them, like the HP-12C, had a horizontal layout. It was one of my childhood dreams to own one someday.
In 1972, Hewlett-Packard released the world’s first scientific pocket calculator, the HP-35 (which got its name because it had 35 keys). In 2007, Hewlett-Packard celebrated the 35th anniversary of the HP-35 by releasing the HP 35s. (I got the picture on the left from here.)
Last 2008, my friend Gilbert gave me an HP 35s. It came with a carrying case and two CD-ROMs: a user’s guide and a video with the title “The HP Calculator Story 1972-2007.” What I like most about the HP 35s is its retro look and its sloped-front keys (you have to press them to fully appreciate them). Another nice thing about it is that its two batteries can be replaced one at a time without erasing the calculator’s memory.