The other day I was able to go to a lecture by Dan Roam, the author of the wildly popular book, "The Back of the Napkin: Solving Problems and Selling Ideas with Pictures." His topic was, "What to do when words don't work" and his seemingly outrageous claim the, "You can solve any problem with pictures."
40 years ago Texas Instruments introduced the first handheld calculator. It could perform addition, subtraction, multiplication, and division. Input was with a small keyboard with 18 keys and a visual output that displayed up to 12 decimal digits using a thermal printhead and paper tape. But how do you test this brand new invention??
