While digging through my desk drawers looking for an orange peeler, I came across my old HP calculator. I’ve owned this since I worked at Exxon and also used it during my MBA program. I was an engineer, so of course this is an RPN calculator.
If you’re not familiar with RPN it stands for Reverse Polish Notation. You can learn more at http://www.calculator.org/rpn.aspx if you’re so inclined. RPN does take a little getting used to when you first start using it, but after a while it really starts to click. Non-engineers who pick one up and try to use it get confused pretty quickly though.
I wonder if people still use these. Mine hasn’t had batteries in it for over a decade, and I never see any in use. Everyone seems to be using soft calculators now. That’s progress I suppose. Maybe kids today look at these like we used to look at slide rules. Yet something else to make me feel old.