What is Code?

Introduction

A computer is a clock with benefits. They all work the same, doing second-grade math, one step at a time: Tick, take a number and put it in box one. Tick, take another number, put it in box two. Tick, operate (an operation might be addition or subtraction) on those two numbers and put the resulting number in box one. Tick, check if the result is zero, and if it is, go to some other box and follow a new set of instructions.

You, using a pen and paper, can do anything a computer can; you just can’t do those things billions of times per second. And those billions of tiny operations add up. They can cause a phone to boop, elevate an elevator, or redirect a missile. That raw speed makes it possible to pull off not one but multiple sleights of hand, card tricks on top of card tricks. Take a bunch of pulses of light reflected from an optical disc, apply some math to unsqueeze them, and copy the resulting pile of expanded impulses into some memory cells—then read from those cells to paint light on the screen. Millions of pulses, 60 times a second. That’s how you make the rubes believe they’re watching a movie.

Apple has always made computers; Microsoft used to make only software (and occasional accessory hardware, such as mice and keyboards), but now it’s in the hardware business, with Xbox game consoles, Surface tablets, and Lumia phones. Facebook assembles its own computers for its massive data centers.

So many things are computers, or will be. That includes watches, cameras, air conditioners, cash registers, toilets, toys, airplanes, and movie projectors.

Samsung makes computers that look like TVs, and Tesla makes computers with wheels and engines. Some things that aren’t yet computers—dental floss, flashlights—will fall eventually.

When you “batch” process a thousand images in Photoshop or sum numbers in Excel, you’re programming, at least a little. When you use computers too much—which is to say a typical amount—they start to change you. I’ve had Photoshop dreams, Visio dreams, spreadsheet dreams, and Web browser dreams. The dreamscape becomes fluid and can be sorted and restructured. I’ve had programming dreams where I move text around the screen.

You can make computers do wonderful things, but you need to understand their limits. They’re not all-powerful, not conscious in the least. They’re fast, but some parts—the processor, the RAM—are faster than others—like the hard drive or the network connection. Making them seem infinite takes a great deal of work from a lot of programmers and a lot of marketers.

The turn-of-last-century British artist William Morris once said you can’t have art without resistance in the materials. The computer and its multifarious peripherals are the materials. The code is the art.

How Do You Type an “A”?

Consider what happens when you strike a key on your keyboard. Say a lowercase “a.” The keyboard is waiting for you to press a key, or release one; it’s constantly scanning to see what keys are pressed down. Hitting the key sends a scancode.

Just as the keyboard is waiting for a key to be pressed, the computer is waiting for a signal from the keyboard. When one comes down the pike, the computer interprets it and passes it farther into its own interior. “Here’s what the keyboard just received—do with this what you will.”

It’s simple now, right? The computer just goes to some table, figures out that the signal corresponds to the letter “a,” and puts it on screen. Of course not—too easy.

It has to take these lines and circles and render them in a little box of pixels in the part of its memory that manages the screen. So far we have at least three representations of one letter: the signal from the keyboard; the version in memory; and the lines-and-circles version sketched on the screen. We haven’t even considered how to store it, or what happens to the letters to the left and the right when you insert an “a” in the middle of a sentence. Or what “lines and circles” mean when reduced to binary data. There are surprisingly many ways to represent a simple “a.” It’s amazing any of it works at all.

Computers are machines. They don’t know what a screen or an “a” are. To put the “a” on the screen, your computer has to pull the image of the “a” out of its memory as part of a font, an “a” made up of lines and circles.

Coders are people who are willing to work backward to that key press. It takes a certain temperament to page through standards documents, manuals, and documentation and read things like “data fields are transmitted least significant bit first” in the interest of understanding why, when you expected “ü,” you keep getting “�.”

From Hardware to Software

Hardware is a tricky business. For decades the work of integrating, building, and shipping computers was a way to build fortunes. But margins tightened. Look at Dell, now back in private hands, or Gateway, acquired by Acer. Dell and Gateway, two world-beating companies, stayed out of software, typically building PCs that came preinstalled with Microsoft Windows—plus various subscription-based services to increase profits.

This led to much cursing from individuals who’d spent $1,000 or more on a computer and now had to figure out how to stop the antivirus software from nagging them to pay up.

Years ago, when Microsoft was king, Steve Ballmer, sweating through his blue button-down, jumped up and down in front of a stadium full of people and chanted, “Developers! Developers! Developers! Developers!”

He yelled until he was hoarse: “I love this company!” Of course he did. If you can sell the software, if you can light up the screen, you’re selling infinitely reproducible nothings. The margins on nothing are great—until other people start selling even cheaper nothings or giving them away. Which is what happened, as free software-based systems such as Linux began to nibble, then devour, the server market, and free-to-use Web-based applications such as Google Apps began to serve as viable replacements for desktop software.

Expectations around software have changed over time. IBM unbundled software from hardware in the 1960s and got to charge more; Microsoft rebundled Internet Explorer with Windows in 1998 and got sued; Apple initially refused anyone else the ability to write software for the iPhone when it came out in 2007, and then opened the App Store, which expanded into a vast commercial territory—and soon the world had Angry Birds. Today, much hardware comes with some software—a PC comes with an operating system, for example, and that OS includes hundreds of subprograms, from mail apps to solitaire. Then you download or buy more.

There have been countless attempts to make software easier to write, promising that you could code in plain English, or manipulate a set of icons, or make a list of rules—software development so simple that a bright senior executive or an average child could do it. Decades of efforts have gone into helping civilians write code as they might use a calculator or write an e-mail. Nothing yet has done away with developers, developers, developers, developers.

Thus a craft, and a professional class that lives that craft, emerged. Beginning in the 1950s, but catching fire in the 1980s, a proportionally small number of people became adept at inventing ways to satisfy basic human desires (know the time, schedule a flight, send a letter, kill a zombie) by controlling the machine. Coders, starting with concepts such as “signals from a keyboard” and “numbers in memory,” created infinitely reproducible units of digital execution that we call software, hoping to meet the needs of the marketplace. Man, did they. The systems they built are used to manage the global economic infrastructure.1 If coders don’t run the world, they run the things that run the world.

Most programmers aren’t working on building a widely recognized application like Microsoft Word. Software is everywhere. It’s gone from a craft of fragile, built-from-scratch custom projects to an industry of standardized parts, where coders absorb and improve upon the labors of their forebears (even if those forebears are one cubicle over). Software is there when you switch channels and your cable box shows you what else is on. You get money from an ATM—software. An elevator takes you up five stories—the same. Facebook releases software every day to something like a billion people, and that software runs inside Web browsers and mobile applications. Facebook looks like it’s just pictures of your mom’s crocuses or your son’s school play—but no, it’s software.