3. BIT-FLINGER

The connection between cars, and ways of interacting with computers, wouldn't have occurred to me at the time I was being taken for rides in that MGB. I had signed up to take a computer programming class at Ames High School. After a few introductory lectures, we students were granted admission into a tiny room containing a teletype, a telephone, and an old-fashioned modem consisting of a metal box with a pair of rubber cups on the top (note: many readers, making their way through that last sentence, probably felt an initial pang of dread that this essay was about to turn into a tedious, codgerly reminiscence about how tough we had it back in the old days; rest assured that I am actually positioning my pieces on the chessboard, as it were, in preparation to make a point about truly hip and up-to-the minute topics like Open Source Software). The teletype was exactly the same sort of machine that had been used, for decades, to send and receive telegrams. It was basically a loud typewriter that could only produce UPPERCASE LETTERS. Mounted to one side of it was a smaller machine with a long reel of paper tape on it, and a clear plastic hopper underneath.

In order to connect this device (which was not a computer at all) to the Iowa State University mainframe across town, you would pick up the phone, dial the computer's number, listen for strange noises, and then slam the handset down into the rubber cups. If your aim was true, one would wrap its neoprene lips around the earpiece and the other around the mouthpiece, consummating a kind of informational soixante-neuf. The teletype would shudder as it was possessed by the spirit of the distant mainframe, and begin to hammer out cryptic messages.

Since computer time was a scarce resource, we used a sort of batch processing technique. Before dialing the phone, we would turn on the tape puncher (a subsidiary machine bolted to the side of the teletype) and type in our programs. Each time we depressed a key, the teletype would bash out a letter on the paper in front of us, so we could read what we'd typed; but at the same time it would convert the letter into a set of eight binary digits, or bits, and punch a corresponding pattern of holes across the width of a paper tape. The tiny disks of paper knocked out of the tape would flutter down into the clear plastic hopper, which would slowly fill up what can only be described as actual bits. On the last day of the school year, the smartest kid in the class (not me) jumped out from behind his desk and flung several quarts of these bits over the head of our teacher, like confetti, as a sort of semi-affectionate practical joke. The image of this man sitting there, gripped in the opening stages of an atavistic fight-or-flight reaction, with millions of bits (megabytes) sifting down out of his hair and into his nostrils and mouth, his face gradually turning purple as he built up to an explosion, is the single most memorable scene from my formal education.

Anyway, it will have been obvious that my interaction with the computer was of an extremely formal nature, being sharply divided up into different phases, viz.: (1) sitting at home with paper and pencil, miles and miles from any computer, I would think very, very hard about what I wanted the computer to do, and translate my intentions into a computer language--a series of alphanumeric symbols on a page. (2) I would carry this across a sort of informational cordon sanitaire (three miles of snowdrifts) to school and type those letters into a machine--not a computer--which would convert the symbols into binary numbers and record them visibly on a tape. (3) Then, through the rubber-cup modem, I would cause those numbers to be sent to the university mainframe, which would (4) do arithmetic on them and send different numbers back to the teletype. (5) The teletype would convert these numbers back into letters and hammer them out on a page and (6) I, watching, would construe the letters as meaningful symbols.

The division of responsibilities implied by all of this is admirably clean: computers do arithmetic on bits of information. Humans construe the bits as meaningful symbols. But this distinction is now being blurred, or at least complicated, by the advent of modern operating systems that use, and frequently abuse, the power of metaphor to make computers accessible to a larger audience. Along the way--possibly because of those metaphors, which make an operating system a sort of work of art--people start to get emotional, and grow attached to pieces of software in the way that my friend's dad did to his MGB.

People who have only interacted with computers through graphical user interfaces like the MacOS or Windows--which is to say, almost everyone who has ever used a computer--may have been startled, or at least bemused, to hear about the telegraph machine that I used to communicate with a computer in 1973. But there was, and is, a good reason for using this particular kind of technology. Human beings have various ways of communicating to each other, such as music, art, dance, and facial expressions, but some of these are more amenable than others to being expressed as strings of symbols. Written language is the easiest of all, because, of course, it consists of strings of symbols to begin with. If the symbols happen to belong to a phonetic alphabet (as opposed to, say, ideograms), converting them into bits is a trivial procedure, and one that was nailed, technologically, in the early nineteenth century, with the introduction of Morse code and other forms of telegraphy.

We had a human/computer interface a hundred years before we had computers. When computers came into being around the time of the Second World War, humans, quite naturally, communicated with them by simply grafting them on to the already-existing technologies for translating letters into bits and vice versa: teletypes and punch card machines.

These embodied two fundamentally different approaches to computing. When you were using cards, you'd punch a whole stack of them and run them through the reader all at once, which was called batch processing. You could also do batch processing with a teletype, as I have already described, by using the paper tape reader, and we were certainly encouraged to use this approach when I was in high school. But--though efforts were made to keep us unaware of this--the teletype could do something that the card reader could not. On the teletype, once the modem link was established, you could just type in a line and hit the return key. The teletype would send that line to the computer, which might or might not respond with some lines of its own, which the teletype would hammer out--producing, over time, a transcript of your exchange with the machine. This way of doing it did not even have a name at the time, but when, much later, an alternative became available, it was retroactively dubbed the Command Line Interface.

When I moved on to college, I did my computing in large, stifling rooms where scores of students would sit in front of slightly updated versions of the same machines and write computer programs: these used dot-matrix printing mechanisms, but were (from the computer's point of view) identical to the old teletypes. By that point, computers were better at time-sharing--that is, mainframes were still mainframes, but they were better at communicating with a large number of terminals at once. Consequently, it was no longer necessary to use batch processing. Card readers were shoved out into hallways and boiler rooms, and batch processing became a nerds-only kind of thing, and consequently took on a certain eldritch flavor among those of us who even knew it existed. We were all off the Batch, and on the Command Line, interface now--my very first shift in operating system paradigms, if only I'd known it.

A huge stack of accordion-fold paper sat on the floor underneath each one of these glorified teletypes, and miles of paper shuddered through their platens. Almost all of this paper was thrown away or recycled without ever having been touched by ink--an ecological atrocity so glaring that those machines [were] soon replaced by video terminals--so-called "glass teletypes"--which were quieter and didn't waste paper. Again, though, from the computer's point of view these were indistinguishable from World War II-era teletype machines. In effect we still used Victorian technology to communicate with computers until about 1984, when the Macintosh was introduced with its Graphical User Interface. Even after that, the Command Line continued to exist as an underlying stratum--a sort of brainstem reflex--of many modern computer systems all through the heyday of Graphical User Interfaces, or GUIs as I will call them from now on.

In The Beginning Was The Command Line
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