Code, by Charles Petzold

A detailed account of how humans invented the computer

I also hope that you might recognize the computer to be one of the crowning achievements of the twentieth century technology and appreciate it as a beautiful thing in itself without metaphors and similes getting in the way.


What an exciting time we live in. It seems like every day there’s a new invention, a new startup raising millions from venture capital to yet again disrupt our world. At the centre of it, computers. Software is eating the world, or so says Marc Andreseen. Every single thing we do in life seems to be related to, in some degree, to computers. You buy on Amazon, you read the news on your smartphone, you pay with your credit card. You swipe, tweet and chat, and google things that have gone viral.

And yet, the layman simply doesn’t know how a computer works.

Everything in this world is magic, except to the magician.

— Robert Ford, Westworld

Once in a while, there’s a new attempt to bridge the gap between the man on the street and the scientific expert. That is, several attempts at conveying the fundaments of engineering, physics or sciences to a wider population. In fact, one of my favourite books in high school was A Short Story of Nearly Everything, a book that the author describes as a “quest to understand everything that has happened from the Big Bang to the rise of civilization”. There have been, too, attempts to encapsulate complex ideas into books aimed at the general public, Brian Greene’s The Elegant Universe being one of them. In both cases, authors realise that gap is simply too wide; you can either err on the side of simplicity, or on the side of accuracy. Which leaves us with infinite approaches to making people understand and learn without getting their hands dirty.

The physicist Leo Szilard once announced to his friend Hans Bethe that he was thinking of keeping a diary: ‘I don’t intend to publish. I am merely going to record the facts for the information of God.’ ‘Don’t you think God knows the facts?’ Bethe asked. ‘Yes,’ said Szilard. ‘He knows the facts, but He does not know this version of the facts.’

Taming the Atom

Unlike Physics, computer’s aren’t universal laws, but the product of centuries of innovations put together. Throughout Code, you’ll learn that although there is a lot going on inside the modern computer, you can always trace each innovation back to an older, simpler machine, until you’re down to something tractable.

That’s what’s so great about studying the history of technology: The further back in time you go, the simpler the technologies become. Thus it’s possible to reach a point where it all makes relatively easy sense.


Computers, and their history, are just shaky towers of abstraction layers: at the very base, they’re simply light bulbs that turn on and off. With each layer, a new opportunity arises to make a process more efficient, while obscuring what’s beneath. Each level presents a new idea grounded on the shoulders of what was there previously, expanding the possibilities just a little bit. The magic, eventually, sprouts. And like all magic tricks, there’s the sensation that knowing how to perform the effect ruins it.

But not all is lost. Learning what’s the shaky tower is made of is like climbing the ladder. We can see there’s no magic to it; but there never was. Once you reach to the top, it’s time to build new abstractions. It’s time to turn into the magician.

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