CODE, The Hidden Language of Computer Hardware and Software, 2d Edition, by Charles Petzold, Microsoft/Pearson 2022

When Petzold published CODE's first edition in 1999, we were worlds away from current computing technologies, but  - 

      "As the years went by, the (first) book started to show its age.  .. Phones and fingers supplemented keyboards and mice.  The internet certainly existed in 1999, but it was nothing       like what it eventually became..."  Charles Petzold

If you learned Basic Assembler Language or FORTRAN or COBOL, your repertoire of subsequent programming skills and later execution and communications languages, would have quickly progressed through a series of faster and more flexible apps -  Pascal, C++, Java and Javascript, Python, almost to the point of obscuring the original workings of a CPU, which is what Petzold wants to bring us in his updated and very creative look at code.  

It's all about zeros and ones, on and off, light and no light.  That's it.  But not the whole story, says Petzold, as he illustrates his look at code history with colorful and simple images from ordinary machine language life.    Starting with a CPU (central processing unit), plus Ram (random access memory), a keyboard, a video display, and a mass storage device - all the basic hardware is in place.  What's missing, of course, is the software that feeds and executes tasks beyond the on-off switch.  Its the coding that makes this machine usable, and Petzold warns us  "All computers execute machine code...but programming in machine code is like eating with a toothpick.  The bites are so small and the process so slow that dinner takes forever... the bytes of machine code perform the tiniest and simplest imaginable computing tasks - loading a number from memory into the processor, adding it to another, storing the result back in memory - so that its difficult to imagine how they contribute to the entire meal."  

Relay wires, vacuum tubes, semi-conductor chips!

CODE is filled with glimpses of the hard-won creation of each new digital technology. Vacuum tubes, all 18,000 of them, which replaced relays, gave us ENIAC, for a few years our biggest computer.  ENIAC gave us the lives of numerous entrepreneurial leaders, like Ken Olsen, co-founder with his brother Stan of Massachusetts' DEC (Digital Equipment Corporation.)  For the early machines, size was unavoidable, a factor that limited use to schools, government agencies and a few corporations.  But as soon as the technology advanced to faster and smaller equipment, we saw a shift in user types and new markets.  

The other big shift in 1947 from vacuum tubes to semi-conductor transistors, pioneered by Bell Labs  physicists - Bardeen and Brattain -  opened the door to today's big non-professional user markets and institutional (government, aviation, banking, etc.) developers.  Although the move from vacuum tubes to core memory to semi-conductors did not complete overnight, for early digital entrepreneurs like the Massachusetts Route 128 pioneers, the path was clearer, and becoming explosively profitable.  

But there is so much more to Petzold's memorable book, including his website, CodeHiddenLanguage.com, a fun, visual approach to understanding how everything we now touch - cars, iphones, security systems, medical devices -  speaks computer codes activated by chips.  What happens in between on and off Petzold shows us in as much detail as we are wanting to learn.  The implication is that our worldwide dependence on these bits and bytes is, unfortunately, despite loops and reboots, as vulnerable as its weakest links.  

Mill Girl Verdict:  A+  More fun than I ever expected.  Covers the history and simplifies tech to the point of enjoyment.  Definitely more fun than Fortran.   

Patricia E. Moody

FORTUNE magazine  "Pioneering Woman in Mfg" 

IndustryWeek IdeaXchange Xpert

A Mill Girl at Blue Heron Journal, on-line resource for business thought-leaders and decision-makers,  patriciaemoody@gmail.com