“We were all about 25 (the more or less to be the same), At the time, we were crashing and banging our way through the “Skylark” and “Lensman” novels of Edward E. Smith. PhD, a cereal chemist who wrote with the grace and refinement of a pneumatic drill.

These stories are pretty much all of a piece: after some preliminary foofaraw to get everyone’s name right, a bunch of overdeveloped Hardy Boys go treking off through the universe to punch out the latest gang of galactic goons, blow up a few planets, kill all kinds of nasty life forms, and just have a heck of a good time”…

“In a pinch, which is where they usually were, our heroes could be counted on to come up with a complete scientific theory, invent the technology to implement it. build the tools to implement the technology, and produce the (usually) weapons to blow away the baddies”

“Is that enough to turn the mind to margarine? It is not. In breaks between books, we would be off to one of Boston’s seedier cinemas to view the latest trash from Toho. In the days before Mazdas and Minoltas. the Japanese (and occasionally the British and Californians) churned out a steady diet of cinematic junk food of which Rodan and Godzilla are only the best known examples. These movies depended for their effects on high quality modelwork. oceans of rays, beams, explosions and general brouhaha, and the determined avoidance of plot, character or significance. They were the movie equivalent of The Skylark of Space.”

“If that’s the case, we asked ourselves, why doesn’t anyone make Skylark movies? Hearing no reply (our innocence of current film technology, economics, and copyright laws as enormous), we often passed the time in the Hingham Street common room in deep wishful thought, inventing special effects and sequences for a grand series of space epics that would never see a sound stage. Nonetheless, these books, movies, and bull-sessions established the mind-set that eventually led to Spacewar!”

“In early 1961 Wayne. Slug, and I. by no coincidence, were all working at Harvard University’s Littauer Statistical laboratory. A large part of our jobs was to run statistics computations for various Harvard persons. The agent of choice for this work was an IBM 704. ”.

“To a generation whose concept of a computer is founded on the Z80 chip, it may be hard to visualize a 704 or to comprehend the place it held in the public imagination as the type specimen of what a computer was: a collection of mysterious hulking gray cabinets approachable only through the intercession of The Operator.

In the specially built computer room. The Operator set switches, pushed buttons, and examined panels of flashing lights, while his Assistants attended various whirring, clanking, and chattering devices […] Add a little incense and a few candles, and you could be forgiven for thinking these were the rites of some oracular shrine.”

“Everything about the 704, from the inscrutable main frame to the glowing tubes (yes. tubes!) in the glass walled core memory case, proclaimed that this was a Very Complicated System operated only by Specially Trained Personnel, among whom programmers and other ordinary mortals were not numbered. In short, a computer was something that you simply did not sit down and fool around with.”

“When computers were still marvels, people would flock to watch them at work whenever the opportunity arose. They were usually disappointed. Whirring tapes and clattering card readers can hold one*s interest only so long.”

“They just did the same dull thing over and over; besides, they were obviously mechanical— at best, overgrown record changers— and thus not mysterious. The main frame, which did all the marvelous work, just sat there. There was nothing to see.”

“On the other hand, something is always happening on a TV screen, which is why people stare at them for hours. On MIT’s annual Open House day. for example, people came to stare for hours at Whirlwind’s CRT screen.”

“Higinbotham had worked on the Manhattan Project, building the timing switches that made the bomb explode at the correct moment. Like many of the scientists who created the bomb, he harboured mixed feelings about what he had done and would spend much of his post-war life campaigning against nuclear proliferation. After the war, he became head of the instrumentation division at the Brookhaven National Laboratory – a US government research facility based on Long Island, New York. Every year Brookhaven would open its doors to the public to show off its work. These visitor days tended to contain static exhibits that did little to excite the public and so, with the 1958 open day looming, Higinbotham decided to make a more engaging attraction”

“He came up with the idea for a fun, interactive exhibit: a tennis game played on the screen of an oscilloscope that he built using transistor circuitry with the help of Brookhaven engineer Robert Dvorak. The game, Tennis for Two, recreated a side-on view of a tennis court with a net in the middle and thin ghostly lines that represented the players’ racquets. The large box-shaped controllers created for the game allowed players to move their racquets using a dial and whack the ball by pressing a button.”

“Brookhaven’s visitors loved it. ‘The high schoolers liked it best, you couldn’t pull them away from it,'”

“In fact Tennis for Two was so popular that it returned for a second appearance at Brookhaven’s 1959 open day. But neither Higinbotham nor anybody else at Brookhaven thought much of the game and after its 1959 encore it was dismantled so its parts could be used in other projects.”

…

On the 14th February 1946, exactly six months after Japan’s surrender, the University of Pennsylvania switched on the first programmable computer: the Electronic Numeric Integrator and Calculator, or ENIAC for short.

The state-of-the-art computer took three years to build, cost $500,000 of US military funding and was created to calculate artillery firing tables for the army. It was a colossus of a machine, weighing 30 tonnes and requiring 63 square metres of floor space. Its innards contained more than 1,500 mechanical relays and 17,000 vacuum tubes – the automated switches that allowed the ENIAC to carry out instructions and make calculations. Since it had no screen or keyboard, instructions were fed in using punch cards. The ENIAC would reply by printing punch cards of its own. These then had to be fed into an IBM accounting machine to be translated into anything of meaning.

The press heralded the ENIAC as a “giant brain”.

It was an apt description given that many computer scientists dreamed of creating an artificial intelligence. Foremost among these computer scientists were the British mathematician Alan Turing and the American computing expert Claude Shannon. The pair had worked together during the war decrypting the secret codes used by German U-boats. The pair’s ideas and theories would form the foundations of modern computing. They saw artificial intelligence as the ultimate aim of computer research and both agreed that getting a computer to defeat a human at Chess would be an important step towards realising that dream.

Foremost among these computer scientists were the British mathematician Alan Turing and the American computing expert Claude Shannon. The pair had worked together during the war decrypting the secret codes used by German U-boats. The pair’s ideas and theories would form the foundations of modern computing. They saw artificial intelligence as the ultimate aim of computer research and both agreed that getting a computer to defeat a human at Chess would be an important step towards realising that dream

The board game’s appeal as a tool for artificial intelligence research was simple. While rules of Chess are straightforward, the variety of possible moves and situations meant that even if a computer could play a million games of Chess every second it would take 10¹⁰⁸ years for it to play every possible version of the game.

“Although perhaps of no practical importance, the question [of computer Chess] is of theoretical interest, and it is hoped that a satisfactory solution of this problem will act as a wedge in attacking other problems of a similar nature and of greater significance.”

In 1947, Turing became the first person to write a computer Chess program. However, Turing’s code was so advanced none of the primitive computers that existed at the time could run it. Eventually in 1952, Turing resorted to testing his Chess game by playing a match with a colleague where he pretended to be the computer. After hours of painstakingly mimicking his computer code, Turing lost to his colleague.

He would never get the opportunity to implement his ideas for computer Chess on a computer. The same year that he tested his program with his colleague, he was arrested and convicted of homosexuality.

At the same time as the scientists of the 1940s and 1950s were teaching computers to play board games, television sets were rapidly making their way into people’s homes. Although the television existed before the Second World War, the conflict saw factories cease production of TV sets to support the war effort by producing radar displays and other equipment for the military

The end of the war, however, produced the perfect conditions for television to take the world by storm. The technological breakthroughs made during the Second World War had brought down the cost of manufacturing TV sets and US consumers now had money to burn after years of austerity

In 1946 just 0.5 per cent of households owned a television. By 1950 this proportion had soared to 9 per cent and by the end of the decade there was a television in almost 90 per cent of US homes.

While the shows on offer from the TV networks springing up across the US seemed enough to get sets flying off the shelves, several people involved in the world of TV began to wonder if the sets could be used for anything else beyond receiving programs

In 1947, the pioneering TV network Dumont became first to try and explore the idea of allowing people to play games on their TV sets. Two of the company’s employees – Thomas Goldsmith and Estle Mann – came up with the Cathode-Ray Tube Amusement Device. Based on a simple electronic circuit, the device would allow people to fire missiles at a target, such as an aeroplane, stuck onto the screen by the player.

The device would use the cathode-ray tube within the TV set to draw lines representing the trajectory of the missile and to create a virtual explosion if the target was hit.[2] Goldsmith and Mann applied for a patent for the idea in January 1947, which was approved the followingyear, but Dumont never turned the device into a commercial product.

A few years later another TV engineer had a similar thought. Born in Germany in 1922, Ralph Baer had spent most of his teenage years watching the rise of the Nazi Party in his home country and the subsequent oppression of his fellow Jews. Eventually, in September 1938, his family fled to the US just weeks before Kristallnacht, the moment when the Nazis’ oppression turned violent and Germany’s Jews began to be rounded up and sent to die in concentration camps.

“My father saw what was coming and got all the paperwork together for us to go to New York,” he said. “We went to the American consulate and sat in his office. I spoke pretty good English. I guess being able to have that conversation with the consulate might have made all the difference because the quota for being let into the US was very small. If we hadn’t got into the quota then it would have been…[motions slicing of the neck].”

In the US, Baer studied television and radio technology and eventually ended up working at military contractors Loral Electronics, where in 1951 he and some colleagues were asked to build a TV set from scratch

“We used test equipment to check our progress and one of the pieces of equipment we used put horizontal lines, vertical lines, cross-hatch patterns, and colour lines on the screen,”

“You could move them around to some extent and use them to adjust the television set. Moving these patterns around was kind of neat and the idea came to me that maybe we wanted to build something into a television set. I don’t know that I thought about it as a game, more something to fool with and to give you something to do with a television set other than watch stupid network programmes.”

Baer’s idea proved fleeting and he quickly cast it aside. But a seed had been sown.

Truman had been vice president for 82 days when President Roosevelt died on April 12, 1945. Truman, presiding over the Senate, as usual, had just adjourned the session for the day and was preparing to have a drink in House Speaker Sam Rayburn’s office when he received an urgent message to go immediately to the White House, where Eleanor Roosevelt told him that her husband had died after a massive cerebral hemorrhage. Truman asked her if there was anything he could do for her; she replied, “Is there anything we can do for you? For you are the one in trouble now!”***

On his first full day, Truman told reporters: ‘Boys, if you ever pray, pray for me now. I don’t know if you fellas ever had a load of hay fall on you, but when they told me what happened yesterday, I felt like the moon, the stars, and all the planets had fallen on me.’

“I hate to make this trip […] If we go, we must win […] I think I can do business with Stalin. Ah; He’s very honest, but he’s also smart as hell.

Although Truman was told briefly on the afternoon of April 12 that the United States had a new, highly destructive weapon, it was not until April 25 that Secretary of War Henry Stimson told him the details:

“We have discovered the most terrible bomb in the history of the world. It may be the fire destruction prophesied in the Euphrates Valley Era, after Noah and his fabulous Ark.”

Truman was very uncomfortable at Potsdam until apparently July 17th. He had been there several days and then that day he received news that the atomic device that had been exploded in New Mexico had worked and that he was going to have an atomic bomb to use in several weeks on the Japanese.

Stimson, who was at Potsdam with Truman, immediately recorded in his diary that President appeared to be ‘all pepped up’. And Churchill later said that Truman, once he heard the news that the atomic bomb worked, was, quote, ‘a changed man’.

About a week after the bomb had gone off in New Mexico and it was clear that Truman was going to have this weapon, Truman approached Stalin at the Potsdam conference and very carefully said to Stalin that he had this new weapon.

Much toTruman’s dismay, Stalin was very passive in response and Truman did not know exactly how to interpret this. This was not the reaction that Truman clearly wanted from Stalin.

What we know now is that Stalin knew exactly about the development of the bomb because of Soviet spies at Los Alamos in New Mexico. We also know that as soon as Stalin walked out of that room after the conversation with Truman, Stalin immediately got in touch with the man who was the director of the Soviet atomic bomb project and said that he must get to work and accelerate the project.

“Just why Peter Samson was wandering around in Building 26 in the middle of the night is a matter that he would find difficult to explain. Some things are not spoken. If you were like the people whom Peter Samson was coming to know and befriend in this, his freshman year at the Massachusetts Institute of Technology in the winter of 1958–59, no explanation would be required. Wan dering around the labyrinth of laboratories and storerooms, searching for the secrets of telephone switching in machine rooms, tracing paths of wires or relays in subterranean steam tunnels— for some, it was common behavior, and there was no need to jus tify the impulse, when confronted with a closed door with an unbearably intriguing noise behind it, to open the door uninvited. And then, if there was no one to physically bar access to whatever was making that intriguing noise, to touch the machine, start flicking switches and noting responses, and eventually to loosen a screw, unhook a template, jiggle some diodes, and tweak a few connections. Peter Samson and his friends had grown up with a specific relationship to the world, wherein things had meaning only if you found out how they worked. And how would you go about that if not by getting your hands on them?

It was in the basement of Building 26 that Samson and his friends discovered the EAM room. Building 26 was a long glass-and-steel structure, one of MIT’s newer buildings, contrasting with the vener able pillared structures that fronted the Institute on Massachusetts Avenue. In the basement of this building void of personality, the EAM room. Electronic Accounting Machinery. A room that housed machines that ran like computers.

Not many people in 1959 had even seen a computer, let alone touched one. Samson, a wiry, curly-haired redhead […] had viewed computers on his visits to MIT from his hometown of Lowell, Massachusetts, less than thirty miles from campus. This made him a “Cambridge urchin,” one of dozens of science-crazy high schoolers in the region who were drawn, as if by gravitational pull, to the Cambridge campus. He had even tried to rig up his own computer with discarded parts of old pinball machines: they were the best source of logic elements he could find”

“Logic elements: the term seems to encapsulate what drew Peter Samson, son of a mill machinery repairman, to electronics. The subject made sense. When you grow up with an insatiable curiosity as to how things work, the delight you find upon discovering something as elegant as circuit logic, where all connections have to complete their loops, is profoundly thrilling. Peter Samson, who early on appreciated the mathematical simplicity of these things, could recall seeing a television show on Boston’s public TV channel, WGBH, which gave a rudimentary introduction to programming a computer in its own language. It fired his imagination; to Peter Samson, a computer was surely like Aladdin’s lamp—rub it, and it would do your bidding.

So he tried to learn more about the field, built machines of his own, entered science project competitions and contests, and went to the place that people of his ilk aspired to: MIT […]  where he would wander the hallways at two o’clock in the morning, looking for something interesting, and where he would indeed discover something that would help draw him deeply into a new form of creative process and a new lifestyle, and would put him into the forefront of a society envisioned only by a few science fiction writers of mild disrepute. He would discover a computer that he could play with”

“The EAM room that Samson had chanced upon was loaded with large keypunch machines the size of squat file cabinets. No one was protecting them: the room was staffed only by day, when a select group who had attained official clearance were privileged enough to submit long manila cards to operators who would then use these machines to punch holes in them according to what data the privileged ones wanted entered on the cards. A hole in the card would represent some instruction to the computer, telling it to put a piece of data somewhere, or perform a function on a piece of data, or move a piece of data from one place to another. An entire stack of these cards made one computer program, a program being a series of instructions which yielded some expected result, just as the instructions in a recipe, when precisely followed, lead to a cake. Those cards would be taken to yet another operator upstairs who would feed the cards into a “reader” that would note where the holes were and dispatch this information to the IBM 704 computer on the first floor of Building 26: the Hulking Giant.

The IBM 704 cost several million dollars, took up an entire room, needed constant attention from a cadre of professional machine operators, and required special air conditioning so that the glowing vacuum tubes inside it would not heat up to data destroying temperatures. When the air conditioning broke down— a fairly common occurrence—a loud gong would sound, and three engineers would spring from a nearby office to frantically take covers off the machine so its innards wouldn’t melt. All these people in charge of punching cards, feeding them into readers, and pressing buttons and switches on the machine were what was commonly called a Priesthood, and those privileged enough to submit data to those most holy priests were the official acolytes. It was an almost ritualistic exchange.

Acolyte: Oh machine, would you accept my offer of information so you may run my program and perhaps give me a computation?

Priest (on behalf of the machine): We will try. We promise nothing.”

“As a general rule, even these most privileged of acolytes were not allowed direct access to the machine itself, and they would not be able to see for hours, sometimes for days, the results of the machine’s ingestion of their “batch” of cards.

This was something Samson knew, and of course it frustrated the hell out of Samson, who wanted to get at the damn machine. For this was what life was all about.

What Samson did not know, and was delighted to discover, was that the EAM room also had a particular keypunch machine called the 407. Not only could it punch cards, but it could also read cards, sort them, and print them on listings. No one seemed to be guarding these machines, which were computers, sort of. Of course, using them would be no picnic: one needed to actually wire up what was called a plug board, a two-inch-by-two-inch plastic square with a mass of holes in it. If you put hundreds of wires through the holes in a certain order, you would get some thing that looked like a rat’s nest but would fit into this electro mechanical machine and alter its personality. It could do what you wanted it to do.

So, without any authorization whatsoever, that is what Peter Samson set out to do, along with a few friends of his from an MIT organization with a special interest in model railroading. It was a casual, unthinking step into a science-fiction future, but that was typical of the way that an odd subculture was pulling itself up by its bootstraps and growing to underground prominence—to become a culture that would be the impolite, unsanctioned soul of computerdom. It was among the first computer hacker escapades of the Tech Model Railroad Club, or TMRC.”

“Peter Samson had been a member of the Tech Model Railroad Club since his first week at MIT in the fall of 1958. The first event that entering MIT freshmen attended was a traditional welcoming lecture, the same one that had been given for as long as anyone at MIT could remember. Look at the person to your left…look at the person to your right…one of you three will not graduate from the Institute. The intended effect of the speech was to create that horrid feeling in the back of the collective freshman throat that signaled unprecedented dread. All their lives, these freshmen had been almost exempt from academic pressure. The exemption had been earned by virtue of brilliance. Now each of them had a person to the right and a person to the left who was just as smart. Maybe even smarter.

Sometime after the lecture came Freshman Midway. All the campus organizations—special-interest groups, fraternities, and such—put up booths in a large gymnasium to try to recruit new members. The group that snagged Peter was the Tech Model Rail road Club. Its members, bright-eyed and crew-cut upperclassmen who spoke with the spasmodic cadences of people who want words out of the way in a hurry, boasted a spectacular display of HO gauge trains they had in a permanent clubroom in Building 20. Peter Samson had long been fascinated by trains, especially subways. So he went along on the walking tour to the building, a shingle-clad temporary structure built during World War II. The hallways were cavernous, and even though the clubroom was on the second floor, it had the dank, dimly lit feel of a basement.

The clubroom was dominated by the huge train layout. It just about filled the room, and if you stood in the little control area called “the notch” you could see a little town, a little industrial area, a tiny working trolley line, a papier-mâché mountain, and of course a lot of trains and tracks. The trains were meticulously crafted to resemble their full-scale counterparts, and they chugged along the twists and turns of the track with picture-book perfection.”

“And then Peter Samson looked underneath the chest-high boards that held the layout. It took his breath away. Underneath this layout was a more massive matrix of wires and relays and crossbar switches than Peter Samson had ever dreamed existed. There were neat regimental lines of switches, achingly regular rows of dull bronze relays, and a long, rambling tangle of red, blue, and yellow wires—twisting and twirling like a rainbow colored explosion of Einstein’s hair. It was an incredibly complicated system, and Peter Samson vowed to find out how it worked.

The Tech Model Railroad Club awarded its members a key to the clubroom after they logged forty hours of work on the layout. Freshman Midway had been on a Friday. By Monday, Peter Samson had his key.”

“The core members hung out at the club for hours, constantly improving The System, arguing about what could be done next, and developing a jargon of their own that seemed incomprehensible to outsiders who might chance on these teen-aged fanatics, with their checked short-sleeve shirts, pencils in their pockets, chino pants, and, always, a bottle of Coca-Cola by their side. (TMRC purchased its own Coke machine for the then forbidding sum of $165; at a tariff of five cents a bottle, the outlay was replaced in three months; to facilitate sales, Saunders built a change machine for Coke buyers that was still in use a decade later.) When a piece of equipment wasn’t working, it was “losing”; when a piece of equipment was ruined, it was “munged” (mashed until no good); the two desks in the corner of the room were not called the office, but the “orifice”; one who insisted on studying for courses was a “tool”; garbage was called “cruft”; and a project undertaken or a product built not solely to fulfill some constructive goal, but with some wild pleasure taken in mere involvement, was called a “hack.”

This latter term may have been suggested by ancient MIT lingo—the word “hack” had long been used to describe the elaborate college pranks that MIT students would regularly devise, such as covering the dome that overlooked the campus with reflecting foil. But as the TMRC people used the word, there was serious respect implied. While someone might call a clever connection between relays a “mere hack,” it would be understood that, to qualify as a hack, the feat must be imbued with innovation, style, and technical virtuosity. Even though one might self-deprecatingly say he was “hacking away at The System” (much as an axe-wielder hacks at logs), the artistry with which one hacked was recognized to be considerable.

The most productive people working on S&P called themselves “hackers” with great pride

Whenever they could, Samson and the others would slip off to the EAM room with their plug boards, trying to use the machine to keep track of the switches underneath the layout. Just as impor tant, they were seeing what the electromechanical counter could do, taking it to its limit.

That spring of 1959, a new course was offered at MIT. It was the first course in programming a computer that freshmen could take. The teacher was a distant man with a wild shock of hair and an equally unruly beard—John McCarthy. A master mathematician, McCarthy was a classically absent-minded professor; stories abounded about his habit of suddenly answering a question hours, sometimes even days after it was first posed to him. He would approach you in the hallway and with no salutation would begin speaking in his robotically precise diction, as if the pause in con versation had been only a fraction of a second, and not a week. Most likely, his belated response would be brilliant.

McCarthy was one of a very few people working in an entirely new form of scientific inquiry with computers. The volatile and controversial nature of his field of study was obvious from the very arrogance of the name that McCarthy had bestowed upon it: Artificial Intelligence. This man actually thought that computers could be smart. Even at such a science-intensive place as MIT, most people considered the thought ridiculous: they considered computers to be useful, if somewhat absurdly expensive, tools for number-crunching huge calculations and for devising missile defense systems (as MIT’s largest computer, the Whirlwind, had done for the early-warning SAGE system), but scoffed at the thought that computers themselves could actually be a scientific field of study. Computer Science did not officially exist at MIT in the late fifties, and McCarthy and his fellow computer specialists worked in the Electrical Engineering Department, which offered the course, No. 641, that Kotok, Samson, and a few other TRMC members took that spring.

McCarthy had started a mammoth program on the IBM 704—the Hulking Giant—that would give it the extraordinary ability to play chess. To critics of the budding field of Artificial Intelligence, this was just one example of the boneheaded optimism of people like John McCarthy. But McCarthy had a certain vision of what computers could do, and playing chess was only the beginning.

All fascinating stuff, but not the vision that was driving Kotok and Samson and the others. They wanted to learn how to work the damn machines, and while this new programming language called LISP that McCarthy was talking about in 641 was interesting, it was not nearly as interesting as the act of programming, or that fantastic moment when you got your printout back from the Priesthood—word from the source itself!—and could then spend hours poring over the results of the program, what had gone wrong with it, how it could be improved. The TMRC hackers were devising ways to get into closer contact with the IBM 704, which soon was upgraded to a newer model called the 709. By hanging out at the Computation Center in the wee hours of the morning, and by getting to know the Priesthood, and by bowing and scraping the requisite number of times, people like Kotok were eventually allowed to push a few buttons on the machine and watch the lights as it worked.

There were secrets to those IBM machines that had been painstakingly learned by some of the older people at MIT with access to the 704 and friends among the Priesthood. Amazingly, a few of these programmers, grad students working with McCarthy, had even written a program that utilized one of the rows of tiny lights: the lights would be lit in such an order that it looked like a little ball was being passed from right to left: if an operator hit a switch at just the right time, the motion of the lights could be reversed— computer Ping-Pong! This obviously was the kind of thing that you’d show off to impress your peers, who would then take a look at the actual program you had written to see how it was done.

There were secrets to those IBM machines that had been painstakingly learned by some of the older people at MIT with access to the 704 and friends among the Priesthood. Amazingly, a few of these programmers, grad students working with McCarthy, had even written a program that utilized one of the rows of tiny lights: the lights would be lit in such an order that it looked like a little ball was being passed from right to left: if an operator hit a switch at just the right time, the motion of the lights could be reversed— computer Ping-Pong! This obviously was the kind of thing that you’d show off to impress your peers, who would then take a look at the actual program you had written to see how it was done.

In 1959, McCarthy was turning his interest from chess to a new way of talking to the computer, the whole new “language” called LISP. Alan Kotok and his friends were more than eager to take over the chess project. Working on the batch-processed IBM, they embarked on the gargantuan project of teaching the 704, and later the 709, and even after that its replacement the 7090, how to play the game of kings. Eventually Kotok’s group became the largest users of computer time in the entire MIT Computation Center.

Still, working with the IBM machine was frustrating. There was nothing worse than the long wait between the time you handed in your cards and the time your results were handed back to you. If you had misplaced as much as one letter in one instruction, the pro gram would crash, and you would have to start the whole process over again. It went hand in hand with the stifling proliferation of goddamn rules that permeated the atmosphere of the Computation Center. Most of the rules were designed to keep crazy young com puter fans like Samson and Kotok and Saunders physically distant from the machine itself. The most rigid rule of all was that no one should be able to actually touch or tamper with the machine itself. This, of course, was what those S&P people were dying to do more than anything else in the world, and the restrictions drove them mad.

One day a former TMRC member who was now on the MIT fac ulty paid a visit to the clubroom. His name was Jack Dennis. When he had been an undergraduate in the early 1950s, he had worked furiously underneath the layout. Dennis lately had been working a computer that MIT had just received from Lincoln Lab, a military development laboratory affiliated with the Institute. The computer was called the TX-0, and it was one of the first transistor run computers in the world. Lincoln Lab had used it specifically to test a giant computer called the TX-2, which had a memory so complex that only with this specially built little brother could its ills be capably diagnosed. Now that its original job was over, the three-million-dollar TX-0 had been shipped over to the Institute on “long-term loan,” and apparently no one at Lincoln Lab had marked a calendar with a return date. Dennis asked the S&P people at TMRC whether they would like to see it.

Hey you nuns! Would you like to meet the Pope?”

“The TX-0 was in Building 26, in the second-floor Research Labo ratory of Electronics (RLE), directly above the first-floor Computation Center, which housed the hulking IBM 704. The RLE lab resembled the control room of an antique spaceship. The TX-0, or Tixo, as it was sometimes called, was for its time a midget machine, since it was one of the first computers to use finger-size transistors instead of hand-size vacuum tubes. Still, it took up much of the room, along with its fifteen tons of supporting air conditioning equipment. The TX-0 workings were mounted on several tall, thin chassis, like rugged metal bookshelves, with tan gled wires and neat little rows of tiny, bottle-like containers in which the transistors were inserted. Another rack had a solid metal front speckled with grim-looking gauges. Facing the racks was an L-shaped console, the control panel of this H.G. Wells spaceship, with a blue countertop for your elbows and papers. On the short arm of the L stood a Flexowriter, which resembled a typewriter converted for tank warfare, its bottom anchored in a military gray housing. Above the top were the control panels, box like protrusions painted an institutional yellow. On the sides of the boxes that faced the user were a few gauges, several lines of quarter-inch blinking lights, a matrix of steel toggle switches the size of large grains of rice, and, best of all, an actual cathode ray tube display, round and smoke-gray.

The TMRC people were awed. This machine did not use cards. The user would first punch in a program onto a long, thin paper tape with a Flexowriter (there were a few extra Flexowriters in an adjoining room), then sit at the console, feed in the program by running the tape through a reader, and be able to sit there while the program ran. If something went wrong with the program, you knew immediately, and you could diagnose the problem by using some of the switches or checking out which of the lights were blinking or lit. The computer even had an audio output: while the program ran, a speaker underneath the console would make a sort of music, like a poorly tuned electric organ whose notes would vibrate with a fuzzy, ethereal din. The chords on this “organ” would change, depending on what data the machine was reading at any given microsecond; after you were familiar with the tones, you could actually hear which part of your program the computer was working on. You would have to discern this, though, over the clacking of the Flexowriter, which could make you think you were in the middle of a machine-gun battle.

Even more amazing was that, because of these “interactive” capabilities, and also because users seemed to be allowed blocks of time to use the TX-0 all by themselves, you could even modify a program while sitting at the computer. A miracle!

There was no way in hell that Kotok, Saunders, Samson, and the others were going to be kept away from that machine. Fortu nately, there didn’t seem to be the kind of bureaucracy sur rounding the TX-0 that there was around the IBM 704. No cadre of officious priests. The technician in charge was a canny, white haired Scotsman named John McKenzie. While he made sure that graduate students and those working on funded projects— Officially Sanctioned Users—maintained access to the machine, McKenzie tolerated the crew of TMRC madmen who began to hang out in the RLE lab, where the TX-0 stood.

Samson, Kotok, Saunders, and a freshman named Bob Wagner soon figured out that the best time of all to hang out in Building 26 was at night, when no person in his right mind would have signed up for an hour-long session on the piece of paper posted every Friday beside the air conditioner in the RLE lab. The TX-0 as a rule was kept running twenty-four hours a day—computers back then were too expensive for their time to be wasted by leaving them idle through the night, and besides, it was a hairy procedure to get the thing up and running once it was turned off. So the TMRC hackers, who soon were referring to themselves as TX-0 hackers, changed their lifestyles to accommodate the computer. They laid claim to what blocks of time they could, and would “vulture time” with nocturnal visits to the lab on the off chance that someone who was scheduled for a 3 A.M. session might not show up.

The hackers recruited a network of informers to give advance notice of potential openings at the computer—if a research project was not ready with its program in time, or a professor was sick, the word would be passed to TMRC and the hackers would appear at the TX-0, breathless and ready to jam into the space behind the console.

Though Jack Dennis was theoretically in charge of the operation, Dennis was teaching courses at the time and preferred to spend the rest of his time actually writing code for the machine. Dennis played the role of benevolent godfather to the hackers: he would give them a brief hands-on introduction to the machine, point them in certain directions, and be amused at their wild program ming ventures. He had little taste for administration, though, and was just as happy to let John McKenzie run things. McKenzie rec ognized early on that the interactive nature of the TX-0 was inspiring a new form of computer programming, and the hackers were its pioneers. So he did not lay down too many edicts.”

“One thing that enabled them to do this was the programming system devised by Jack Dennis and another professor, Tom Stockman. When the TX-0 arrived at MIT, it had been stripped down since its days at Lincoln Lab: the memory had been reduced considerably, to 4,096 “words” of eighteen bits each. (A “bit” is a binary digit, either a 1 or 0. These binary numbers are the only things computers understand. A series of binary numbers is called a “word.”) And the TX-0 had almost no software. So Jack Dennis, even before he introduced the TMRC people to the TX-0, had been writing “systems programs”—the software to help users utilize the machine

The first thing Dennis worked on was an assembler. This was something that translated assembly language—which used three letter symbolic abbreviations that represented instructions to the machine—into machine language, which consisted of the binary numbers 0 and 1. The TX-0 had a rather limited assembly language: since its design allowed only 2 bits of each 18-bit word to be used for instructions to the computer, only four instructions could be used (each possible 2-bit variation—00, 01, 10, and 11— represented an instruction). Everything the computer did could be broken down to the execution of one of those four instructions: it took one instruction to add two numbers, but a series of perhaps twenty instructions to multiply two numbers.

Staring at a long list of computer commands written as binary numbers—for example, 10011001100001—could make you into a babbling mental case in a matter of minutes. But the same command in assembly language might look like this: ADD Y. After loading the computer with the assembler that Dennis wrote, you could write programs in this simpler symbolic form, and wait smugly while the computer did the translation into binary for you. Then you’d feed that binary “object” code back into the computer. The value of this was incalculable: it enabled programmers to write in something that looked like code, rather than an endless, dizzying series of 1s and 0s.

The other program that Dennis worked on with Stockman was something even newer—a debugger. The TX-0 came with a debugging program called UT-3, which enabled you to talk to the computer while it was running by typing commands directly into the Flexowriter. But it had terrible problems—for one thing, it only accepted typed-in code that used the octal numeric system. “Octal” is a base-8 number system (as opposed to binary, which is base 2, and Arabic—ours—which is base 10), and it is a difficult system to use. So Dennis and Stockman decided to write some thing better than UT-3 that would enable users to use the symbolic, easier-to-work-with assembly language. This came to be called FLIT, and it allowed users to actually find program bugs during a session, fix them, and keep the program running. (Dennis would explain that “FLIT” stood for Flexowriter Interrogation Tape, but clearly the name’s real origin was the insect spray with that brand name.) FLIT was a quantum leap forward, since it liberated programmers to actually do original composing on the machine—just like musicians composing on their musical instruments. With the use of the debugger, which took up one third of the 4,096 words of the TX-0 memory, hackers were free to create a new, more daring style of programming.

And what did these hacker programs do? Well, sometimes, it didn’t matter much at all what they did. Peter Samson hacked the night away on a program that would instantly convert Arabic numbers to Roman numerals, and Jack Dennis, after admiring the skill with which Samson had accomplished this feat, said, “My God, why would anyone want to do such a thing?” But Dennis knew why. There was ample justification in the feeling of power and accomplishment Samson got when he fed in the paper tape, monitored the lights and switches, and saw what were once plain old blackboard Arabic numbers coming back as the numerals the Romans had hacked with.

In fact, it was Jack Dennis who suggested to Samson that there were considerable uses for the capability of the TX-0 to send noise to the audio speaker. While there were no built-in controls for pitch, amplitude, or tone character, there was a way to control the speaker—sounds would be emitted depending on the state of the 14th bit in the 18-bit words the TX-0 had in its accumulator in a given microsecond. The sound was on or off depending on whether bit 14 was a 1 or 0. So Samson set about writing programs that varied the binary numbers in that slot in different ways to produce different pitches.

At that time, only a few people in the country had been experimenting with using a computer to output any kind of music, and the methods they had been using required massive computations before the machine would so much as utter a note. Samson, who reacted with impatience to those who warned he was attempting the impossible, wanted a computer playing music right away. So he learned to control that one bit in the accumulator so adeptly that he could command it with the authority of Charlie Parker on the saxophone. In a later version of this music compiler, Samson rigged it so that if you made an error in your programming syntax, the Flexowriter would switch to a red ribbon and print, “To err is human to forgive divine.”

When outsiders heard the melodies of Johann Sebastian Bach in a single-voice, monophonic square wave, no harmony, they were universally unfazed. Big deal! Three million dollars for this giant hunk of machinery, and why shouldn’t it do at least as much as a five-dollar toy piano? It was no use to explain to these outsiders that Peter Samson had virtually bypassed the process by which music had been made for eons. Music had always been made by directly creating vibrations that were sound. What happened in Samson’s program was that a load of numbers, bits of information fed into a computer, comprised a code in which the music resided. You could spend hours staring at the code, and not be able to divine where the music was. It only became music while millions of blindingly brief exchanges of data were taking place in the accumulator sitting in one of the metal, wire, and silicon racks that comprised the TX-0. Samson had asked the computer, which had no apparent knowledge of how to use a voice, to lift itself in song, and the TX-0 had complied.

So it was that a computer program was not only metaphorically a musical composition—it was literally a musical composition! It looked like—and was—the same kind of program that yielded complex arithmetical computations and statistical analyses. These digits that Samson had jammed into the computer were a universal language that could produce anything—a Bach fugue or an antiaircraft system.

Samson did not say any of this to the outsiders who were unimpressed by his feat. Nor did the hackers themselves discuss this—it is not even clear that they analyzed the phenomenon in such cosmic terms. Peter Samson did it, and his colleagues appreciated it, because it was obviously a neat hack. That was justification enough.”

Now, IBM had done and would continue to do many things to advance computing. By its sheer size and mighty influence, it had made computers a permanent part of life in America. To many people, the words “IBM” and “computer” were virtually synonymous. IBM’s machines were reliable workhorses, worthy of the trust that businessmen and scientists invested in them. This was due in part to IBM’s conservative approach: it would not make the most technologically advanced machines, but would rely on proven concepts and careful, aggressive marketing. As IBM’s dominance of the computer field was established, the company became an empire unto itself, secretive and smug

What really drove the hackers crazy was the attitude of the IBM priests and sub-priests, who seemed to think that IBM had the only “real” computers, and the rest were all trash. You couldn’t talk to those people—they were beyond convincing. They were batch-processed people, and it showed not only in their preference of machines, but in their ideas about the way a computation center, and a world, should be run.

This antibureaucratic bent coincided neatly with the personalities of many of the hackers, who since childhood had grown accustomed to building science projects while the rest of their classmates were banging their heads together and learning social skills on the field of sport.

“like you opened the door and walked through this grand new universe . . .”

Samson’s music program was an example. But to hackers, the art of the program did not reside in the pleasing sounds emanating from the online speaker. The code of the program held a beauty of its own.

A certain esthetic of programming style had emerged. Because of the limited memory space of the TX-0 (a handicap that extended to all computers of that era), hackers came to deeply appreciate innovative techniques that allowed programs to do complicated tasks with very few instructions. The shorter a program was, the more space you had left for other programs, and the faster a program ran.

Sometimes program bumming became competitive, a macho contest to prove oneself so much in command of the system that one could recognize elegant shortcuts to shave off an instruction or two, or, better yet, rethink the whole problem and devise a new algorithm that would save a whole block of instructions. This could most emphatically be done by approaching the problem from an offbeat angle that no one had ever thought of before, but that in retrospect made total sense. There was definitely an artistic impulse residing in those who could utilize this genius-from-Mars technique—a black-magic, visionary quality that enabled them to discard the stale outlook of the best minds on earth and come up with a totally unexpected new algorithm.

This belief was subtly manifest. Rarely would a hacker try to impose a view of the myriad advantages of the computer way of knowledge to an outsider. Yet, this premise dominated the everyday behavior of the TX-0 hackers, as well as the generations of hackers that came after them.

The computer had changed their lives, made their lives adventurous. It had made them masters of a certain slice of fate. Peter Samson later said, “We did it twenty-five to thirty percent for the sake of doing it because it was something we could do and do well, and sixty percent for the sake of having something which was in its metaphorical way alive, our offspring, which would do things on its own when we were finished.

“That’s the great thing about programming, the magical appeal it has . . . Once you fix a behavioral problem [a computer or program] has, it’s fixed forever, and it is exactly an image of what you meant.”

Like Aladdin’s lamp, you could get it to do your bidding

This was not easily done. Even at such an advanced institution as MIT, some professors considered a manic affinity for computers as frivolous, even demented. TMRC hacker Bob Wagner once had to explain to an engineering professor what a computer was. Wagner experienced this clash of computer versus anticomputer even more vividly when he took a Numerical Analysis class in which the professor required each student to do homework using rattling, clunky electromechanical calculators. Kotok was in the same class, and both of them were appalled at the prospect of working with those low-tech machines. “Why should we,” they asked, “when we’ve got this computer?”

So Wagner began working on a computer program that would emulate the behavior of a calculator. The idea was outrageous. To some, it was a misappropriation of valuable machine time. According to the standard thinking on computers, their time was so precious that one should only attempt things that took maximum advantage of the computer, things that otherwise would take roomfuls of mathematicians days of mindless calculating. Hackers felt otherwise: anything that seemed interesting or fun was fodder for computing—and using interactive computers, with no one looking over your shoulder and demanding clearance for your specific project, you could act on that belief. After two or three months of tangling with intricacies of floating-point arithmetic (necessary to allow the program to know where to place the decimal point) on a machine that had no simple method to perform elementary multiplication, Wagner had written three thousand lines of code that did the job. He had made a ridiculously expensive computer perform the function of a calculator that was one thousandth the price. To honor this irony, he called the program “Expensive Desk Calculator,” and proudly did the homework for his class on it.

His grade—zero. “You used a computer!” the professor told him. “This can’t be right.”

Wagner didn’t even bother to explain. How could he convey to his teacher that the computer was making realities out of what were once incredible possibilities? Or that another hacker had even written a program called “Expensive Typewriter” that converted the TX-0 to something you could write text on, could process your writing in strings of characters and print it out on the Flexowriter—could you imagine a professor accepting a classwork report written by the computer? How could that professor—how could, in fact, anyone who hadn’t been immersed in this uncharted man-machine universe—understand how Wagner and his fellow hackers were routinely using the computer to simulate, according to Wagner, “strange situations which one could scarcely envision otherwise”? The professor would learn in time, as would everyone, that the world opened up by the computer was a limitless one.

In the monastic confines of the Massachusetts Institute of Technology, people had the freedom to live out this dream—the hacker dream. No one dared suggest that the dream might spread. Instead, people set about building, right there at MIT, a hacker Xanadu, the likes of which might never be duplicated.

In the summer of 1961, Alan Kotok and the other TMRC hackers learned that a new company was soon to deliver to MIT, absolutely free, the next step in computing, a machine that took the interactive principles of the TX-0 several steps further. A machine that might be even better for hackers than the TX-0 was.

Alan Kotok had distinguished himself as a true wizard on the TX-0, so much so that he, along with Saunders, Samson, Wagner, and a few others, had been hired by Jack Dennis to be the Systems Programming Group of the TX-0. The pay would be a munificent $1.60 an hour. For a few of the hackers, the job was one more excuse not to go to classes—some hackers, like Samson, would never graduate, and be too busy hacking to really regret the loss. Kotok, though, was able not only to manage his classes, but to establish himself as a “canonical” hacker. Around the TX-0 and TMRC, he was acquiring legendary status. One hacker who was just arriving at MIT that year remembers Kotok giving newcomers a demonstration of how the TX-0 worked: “I got the impression he was hyperthyroid or something,” recalled Bill Gosper, who would become a canonical hacker himself, “because he spoke very slowly and he was chubby and his eyes were half-closed. That was completely and utterly the wrong impression. [Around the TX-0] Kotok had infinite moral authority. He had written the chess program.

He understood hardware.” (This last was not an inconsiderable compliment—“understanding hardware” was akin to fathoming the Tao of physical nature.)

The summer that the word came out about the PDP-1, Kotok was working for Western Electric, kind of a dream job, since of all possible systems the phone system was admired most of all. The Model Railroad Club would often go on tours of phone company exchanges, much in the way that people with an interest in painting might tour a museum […] But as much as phone company esoterica fascinated Kotok, the prospect of the PDP-1 took precedence. Perhaps he sensed that nothing, even phone hacking, would be the same afterward. The people who designed and marketed this new machine were not your ordinary computer company button-downs. The company was a brand-new firm called Digital Equipment Corporation (DEC), and some of the TX-0 users knew that DEC’s first products were special interfaces made specifically for that TX-0. It was exciting enough that some of DEC’s founders had a view of computing that differed from the gray-flannel, batch-processed IBM mentality; it was positively breathtaking that the DEC people seemed to have looked at the freewheeling, interactive, improvisational, hands-on-über-alles style of the TX-0 community, and designed a computer that would reinforce that kind of behavior. The PDP-1 (the initials were short for Programmed Data Processor, a term considered less threatening than “computer,” which had all kinds of hulking-giant connotations) would become known as the first minicomputer, designed not for huge number crunching tasks, but for scientific inquiry, mathematical formulation . . . and hacking. It would be so compact that the whole setup was no larger than three refrigerators—it wouldn’t require as much air conditioning, and you could even turn it on without a whole crew of sub-priests being needed to sequence several power supplies in the right order or start the time-base generator, among other exacting tasks. The retail price of the computer was an astoundingly low $120,000—cheap enough so people might stop complaining about how precious every second of computer time was. But the machine, which was the second PDP-1 manufactured (the first one was sold to the nearby scientific firm of Bolt Beranek and Newman, or BBN), cost MIT nothing: it was donated by DEC to the RLE lab.

So it was clear that hackers would have even more time on it than they did on the TX-0

The PDP-1 would be delivered with a simple collection of systems software, which the hackers considered completely inadequate. The TX-0 hackers had become accustomed to the most advanced interactive software anywhere, a dazzling set of systems programs, written by hackers themselves and implicitly tailored to their relentless demands for control of the machine. Young Peter Deutsch, the twelve-year-old who had discovered the TX-0, had made good on his promise to write a spiffier assembler, and Bob Saunders had worked up a smaller, faster version of the FLIT debugger called Micro-FLIT. These programs had benefited from an expanded instruction set. One day, after considerable planning and designing by Saunders and Jack Dennis, the TX-0 had been turned off, and a covey of engineers exposed its innards and began hardwiring new instructions into the machine. This formidable task expanded the assembly language by several instructions. When the pliers and screwdrivers were put away and the computer carefully turned on, everyone madly set about revamping programs and bumming old programs using the new instructions.

The PDP-1 instruction set, Kotok learned, was not too different from that of the expanded TX-0, so Kotok naturally began writing systems software for the PDP-1 that very summer, using all the spare time he could manage. Figuring that everyone would jump in and begin writing as soon as the machine got there, he worked on a translation of the Micro-FLIT debugger so that writing the software for the “One” would be easier. Samson promptly named Kotok’s debugger “DDT,” and the name would stick, though the program itself would be modified countless times by hackers who wanted to add features or bum instructions out of it.

Jack Dennis liked some of the software written by BBN for the prototype PDP-1, particularly the assembler. Kotok, though, felt like retching when he saw that assembler run—the mode of operation didn’t seem to fit the on-the-fly style he liked—so he and a few others told Dennis that they wanted to write their own. “That’s a bad idea,” said Dennis, who wanted an assembler up and running right away, and figured that it would take weeks for the hackers to do it.

Kotok and the others were adamant. This was a program that they’d be living with. It had to be just perfect. (Of course no program ever is, but that never stopped a hacker.)

“I’ll tell you what,” said Kotok, this twenty-year-old Buddhashaped wizard, to the skeptical yet sympathetic Jack Dennis, “If we write this program over the weekend and have it working, would you pay us for the time?”

The pay scale at that time was such that the total would be something under five hundred dollars. “That sounds like a fair deal,” said Dennis, Kotok, Samson, Saunders, Wagner, and a couple of others began on a Friday night late in September. They figured they would work from the TX-0 assembler that Dennis had written the original of and that twelve-year-old Peter Deutsch, among others, had revamped. They wouldn’t change inputs or outputs, and they wouldn’t redesign algorithms; each hacker would take a section of the TX-0 program and convert it to PDP-1 code. And they wouldn’t sleep. Six hackers worked around two hundred fifty man-hours that weekend, writing code, debugging, and washing down take-out Chinese food with massive quantities of Coca-Cola shipped over from the TMRC clubroom. It was a programming orgy, and when Jack Dennis came in that Monday, he was astonished to find an assembler loaded into the PDP-1, which, as a demonstration, was assembling its own code into binary.

The PDP-1 beckoned the hackers to program without limit. Samson was casually hacking things like the Mayan calendar (which worked on a base-20 number system) and working overtime on a version of his TX-0 music program that took advantage of the PDP-1’s extended audio capabilities to create music in three voices—three-part Bach fugues, melodies interacting . . . computer music erupting from the old Kluge Room! The people at DEC had heard about Samson’s program and asked him to complete it on the PDP-1, so Samson eventually worked it so that someone could type a musical score into the machine by a simple translation of notes into letters and digits, and the computer would respond with a three-voice organ sonata. Another group coded up Gilbert and Sullivan operettas.

Samson proudly presented the music compiler to DEC to distribute to anyone who wanted it. He was proud that other people would be using his program. The team that worked on the new assembler felt likewise. For instance, they were pleased to have paper tape bearing the program in the drawer so anyone using the machine could access it, try to improve it, bum a few instructions from it, or add a feature to it. They felt honored when DEC asked for the program so it could offer it to other PDP-1 owners. The question of royalties never came up. To Samson and the others, using the computer was such a joy that they would have paid to do it. The fact that they were getting paid the princely sum of $1.60 an hour to work on the computer was a bonus. As for royalties, wasn’t software more like a gift to the world, something that was reward in itself? The idea was to make a computer more usable, to make it more exciting to users, to make computers so interesting that people would be tempted to play with them, explore them, and eventually hack on them. When you wrote a fine program you were building a community, not churning out a product.

The TMRC hackers were not the only ones who had been devising plans for the new PDP-1. During that summer of 1961, a plan for the most elaborate hack yet—a virtual showcase of what could come out of a rigorous application of the Hacker Ethic—was being devised. The scene of these discussions was a tenement building on Higham Street in Cambridge, and the original perpetrators were three itinerant programmers in their mid-twenties who’d been hanging around various computation centers for years. Two of the three lived in the tenement, so in honor of the pompous proclamations emanating from nearby Harvard University the trio mockingly referred to the building as the Higham Institute.

One of the Fellows of this bogus institution was Steve Russell, nicknamed, for unknown reasons, Slug. He had that breathless chipmunk speech pattern so common among hackers, along with thick glasses, modest height, and a fanatic taste for computers, bad movies, and pulp science fiction. All three interests were shared by the resident attendees at those bull sessions on Higham Street.

Russell had long been a “coolie” (to use a TMRC term) of Uncle John McCarthy. McCarthy had been trying to design and implement a higher-level language that might be sufficient for artificial intelligence work. He thought he had found it in LISP. The language was named for its method of List Processing; by simple yet powerful commands, LISP could do many things with few lines of code; it could also perform powerful recursions—references to things within itself—which would allow programs written in that language to actually “learn” from what happened as the program ran. The problem with LISP at that time was that it took up an awful amount of space on a computer, ran very slowly, and generated voluminous amounts of extra code as the programs ran, so much so that it needed its own “garbage collection” program toperiodically clean out the computer memory.

Russell was helping Uncle John write a LISP interpreter for the Hulking Giant IBM 704. It was, in his words, “a horrible engineering job,” mostly due to the batch-processing tedium of the 704.

Compared to that machine, the PDP-1 looked like the Promised Land to Slug Russell. More accessible than the TX-0, and no batch processing! Although it didn’t seem big enough to do LISP, it had other marvelous capabilities, some of which were objects of discussion of the Higham Institute. What particularly intrigued Russell and his friends was the prospect of making up some kind of elaborate “display hack” on the PDP-1, using the CRT screen. After considerable midnight discourse, the three-man Higham Institute put itself on record as insisting that the most effective demonstration of the computer’s magic would be a visually striking game.

But already on the PDP-1, which had a screen that was easier to program than the TX-0’s, there had been some significant display hacks. The most admired effort was created by one of the twin gurus of artificial intelligence at MIT, Marvin Minsky (the other one was, of course, McCarthy). Minsky was more outgoing than his fellow AI guru, and more willing to get into the hacker mode of activity. He was a man with very big ideas about the future of computing—he really believed that one day machines would be able to think, and he would often create a big stir by publicly calling human brains “meat machines,” implying that machines not made of meat would do as well some day. An elfish man with twinkling eyes behind thick glasses, a starkly bald head, and an omnipresent turtleneck sweater, Minsky would say this with his usual dry style, geared simultaneously to maximize provocation and to leave just a hint that it was all some cosmic goof—of course machines can’t think, heh-heh. Marvin was the real thing; the PDP-1 hackers would often sit in on his course, Intro to AI 6.544, because not only was Minsky a good theoretician, but he knew his stuff. By the early 1960s, Minsky was beginning to organize what would come to be the world’s first laboratory in artificial intelligence; and he knew that to do what he wanted, he would need programming geniuses as his foot soldiers—so he encouraged hackerism in any way he could.

One of Minsky’s contributions to the growing canon of interesting hacks was a display program on the PDP-1 called the Circle Algorithm. It was discovered by mistake, actually—while trying to bum an instruction out of a short program to make straight lines into curves or spirals, Minsky inadvertently mistook a “Y” character for a “Y prime,” and instead of the display squiggling into inchoate spirals as expected, it drew a circle: an incredible discovery, which was later found to have profound mathematical implications. Hacking further, Minsky used the Circle Algorithm as a stepping-off point for a more elaborate display in which three particles influenced each other and made fascinating, swirling patterns on the screen, self-generating roses with varying numbers of leaves. “The forces particles exerted on others were totally outlandish,” Bob Wagner later recalled. “You were simulating a violation of natural law!” Minsky called the hack a “Tri-Pos: Three-Position Display” program, but the hackers affectionately renamed it the Minskytron.

“Bouncing Ball (for the Whirlwind) may be the very first computer-CRT demonstration program. It didn’t do much: a dot appeared at the top of the screen, fell to the bottom and bounced (with a “thok” from the console speaker). It bounced off the sides and floor of the displayed box. gradually losing momentum until it hit the floor and rolled off the screen through a hole in the bottom line. And that’s all. Pong was not even an idea in 1960.”

“The TX-O’s counterpart to Bouncing Ball was the Mouse in the Maze, written by Douglas T. Ross and John E. Ward. Essentially, it was a short cartoon: a stylized mouse searched through a rectangular maze until it found a piece of cheese which it then ate. leaving a few crumbs. You constructed the maze and placed the cheese (or cheeses— you could have more than one) with the light pen. A variation replaced the cheese with a martini; after drinking the first one the mouse would stagger to the next.”

“Besides the Mouse, the TX-O also had HAX (and latter the Minskytron). which displayed changing patterns according to the settings of two console switch registers. Well-chosen settings could produce interesting shapes or arrangements of dots, sometimes accompanied by amusing sounds from the console speaker.”

“Finally, there was the inevitable TicTac-Toe. with the user playing the computer. The TX-O version used the Flexowriter rather than the scope.”

“These four programs pointed the way. Bouncing Ball was a pure demonstration: you pushed the button, and it did all the rest. The mouse was more fun. because you could make it different every time. HAX was a real toy; you could play with it while it was running and make it change on the fly. And Tic-Tac-Toe was an actual game, however simpleminded. The ingredients were there; we just needed an idea.”

“It was clear from the start that while the Ball and Mouse and HAX were clever and amusing, they really weren’t very good as demonstration programs […] the Hingham Institute Study Group on Space Warfare devised its Theory of Computer Toys. A good demonstration program ought to satisfy three criteria :

1. It should demonstrate, that is. it should show off as many of the computer’s resources as possible, and tax those resources to the limit:
2. Within a consistent framework, it should be interesting, which means that every run should be different:
3. It should involve the onlooker in a pleasurable and active way— in short, it should be a game.

Wayne said. “Look, you need action and you need some kind of skill level. It should be a game where you have to control things moving around on the scope, like. oh. spaceships. Something like an explorer game, or a race or contest. ..a fight, maybe’.'”

“SPACEWAR!”

“The basic rules developed quickly. There would be at least two spaceships, each controlled by a set of console switches. The ships would have a supply of rocket fuel and some sort of weapon: a ray or a beam, possibly a missile. For really hopeless situations, a panic button would be nice… Hyperspace! And that, pretty much, was that.”

But months later, Russell hadn’t even started. He would watch the Minskytron make patterns, he’d flip switches to see new patterns develop, and every so often he’d flip more switches when the program got wedged into inactivity. He was fascinated, but thought the hack too abstract and mathematical. “This demo is a crock,” he finally decided—only thirty-two or so instructions, and it didn’t really do anything.

Slug Russell knew that his war-in-outer-space game would do something. In its own kitschy, sci-fi terms, it would be absorbing in a way no previous hack had ever been. The thing that got Slug into computers in the first place was the feeling of power you got from running the damn things. You can tell the computer what to do, and it fights with you, but it finally does what you tell it to. Of course it will reflect your own stupidity, and often what you tell it to do will result in something distasteful. But eventually, after tortures and tribulations, it will do exactly what you want. The feeling you get then is unlike any other feeling in the world. It can make you a junkie. It made Slug Russell a junkie, and he could see that it had done the same thing to the hackers who haunted the Kluge Room until dawn. It was that feeling that did it, and Slug Russell guessed the feeling was power.

Slug was not as driven as some of the other hackers. Sometimes he needed a push. After he made the mistake of opening up his big mouth about this program he was going to write, the PDP-1 hackers, always eager to see another hack added to the growing pile of paper tapes in the drawer, urged him to do it. After mumbling excuses for a while, he said he would, but he’d first have to figure out how to write the elaborate sine-cosine routines necessary to plot the ships’ motion.

Kotok knew that hurdle could be easily solved. Kotok at that point had been getting fairly cozy with the people at DEC, several miles away at Maynard. DEC was informal, as computer manufacturers went, and did not regard MIT hackers as the grungy, frivolous computer-joyriders that IBM might have taken them for. For instance, one day when a piece of equipment was broken, Kotok called up Maynard and told DEC about it; they said, “Come up and get a replacement.” By the time Kotok got up there, it was well after 5 P.M. and the place was closed. But the night watchman let him go in, find the desk of the engineer he’d been talking to, and root through the desk until he found the part. Informal, the way hackers like it. So it was no problem for Kotok to go up to Maynard one day, where he was positive someone would have a routine for sine and cosine that would run on the PDP-1. Sure enough, someone had it, and since information was free, Kotok took it back to Building 26.

“Here you are, Russell,” Kotok said, paper tapes in hand. “Now what’s your excuse?”

At that point, Russell had no excuse. So he spent his off-hours writing this fantasy PDP-1 game, the likes of which no one had seen before. Soon he was spending his “on” hours working on the game. He began in early December, and when Christmas came, he was still hacking. When the calendar wrapped around to 1962, he was still hacking. By that time, Russell could produce a dot on the screen that you could manipulate: by flicking some of the tiny toggle switches on the control panel, you could make the dots accelerate and change direction.

He then set about making the shapes of the two rocket ships: both were classic cartoon rockets, pointed at the top and blessed with a set of fins at the bottom. To distinguish them from each other, he made one chubby and cigar-shaped, with a bulge in the middle, while the second he shaped like a thin tube. Russell used the sine and cosine routines to figure out how to move those shapes in different directions. Then he wrote a subroutine to shoot a “torpedo” (a dot) from the rocket nose with a switch on the computer.The computer would scan the position of the torpedo and the enemy ship; if both occupied the same area, the program would call up a subroutine that replaced the unhappy ship with a random splatter of dots representing an explosion. (That process was called “collision detection.”)

All of this was actually a significant conceptual step toward more sophisticated “real-time” programming, where what happens on a computer matches the frame of reference in which human beings are actually working. In another sense, Russell was emulating the online, interactive debugging style that the hackers were championing—the freedom to see what instruction your program stopped dead on, and to use switches or the Flexowriter to jimmy in a different instruction, all while the program was running along with the DDT debugger. The game Spacewar, a computer program itself, helped show how all games—and maybe everything elseworked like computer programs. When you went a bit astray, you modified your parameters and fixed it. You put in new instructions. The same principle applied to target shooting, chess strategy, and MIT course work. Computer programming was not merely a technical pursuit, but an approach to the problems of living.

In the later stages of programming, Saunders helped Slug Russell out, and they hacked a few intense six-to-eight-hour sessions. Sometime in February, Russell unveiled the basic game. There were the two ships, each with thirty-one torpedoes. There were a few random dots on the screen representing stars in this celestial battlefield. You could maneuver the ships by flicking four switches on the console of the PDP-1, representing clockwise turn, counterclockwise turn, accelerate, and fire torpedo.

Slug Russell knew that by showing a rough version of the game, and dropping a paper tape with the program into the box with the PDP-1 system programs, he was welcoming unsolicited improvements. Spacewar was no ordinary computer simulation—you could actually be a rocket-ship pilot. It was Doc Smith come to life. But the same power that Russell had drawn on to make his program—the power that the PDP-1 lent a programmer to create his own little universe—was also available to other hackers, who naturally felt free to improve Slug Russell’s universe. They did so instantly.

Peter Samson, for instance, loved the idea of Spacewar, but could not abide the randomly generated dots that passed themselves off as the sky. Real space had stars in specific places. “We’ll have the real thing,” Samson vowed. He obtained a thick atlas of the universe, and set about entering data into a routine he wrote that would generate the actual constellations visible to someone standing on the equator on a clear night. All stars down to the fifth magnitude were represented; Samson duplicated their relative brightness by controlling how often the computer lit the dot on the screen which represented the star. He also rigged the program so that, as the game progressed, the sky would majestically scroll—at any one time the screen exposed forty-five percent of the sky. Besides adding verisimilitude, this “Expensive Planetarium” program also gave rocket fighters a mappable background from which to gauge position. The game could truly be called, as Samson said, Shootout-at-El-Cassiopeia.

Another programmer, named Dan Edwards, was dissatisfied with the unanchored movement of the two dueling ships. It made the game merely a test of motor skills. He figured that adding a gravity factor would give the game a strategic component. So he programmed a central star—a sun—in the middle of the screen; you could use the sun’s gravitational pull to give you speed as you circled it, but if you weren’t careful and got too close, you’d be drawn into the sun, which was certain death.

Before all the strategic implications of this variation could be employed, Shag Garetz, one of the Higham Institute trio, contributed a wild-card type of feature. He had read in Doc Smith’s novels how space hot-rodders could suck themselves out of one galaxy and into another by virtue of a “hyper-spatial tube,” which would throw you into “that highly enigmatic Nth space.” So he added a “hyperspace” capability to the game, allowing a player to avoid a dire situation by pushing a panic button that would zip him to this hyperspace. You were allowed to go into hyperspace three times in the course of a game; the drawback was that you never knew where you might come out. Sometimes you’d reappear right next to the sun, just in time to see your ship hopelessly pulled to an untimely demise on the sun’s surface. In tribute to Marvin Minsky’s original hack, Garetz programmed the hyperspace feature so that a ship entering hyperspace would leave a “warp-induced photonic stress emission signature”—a leftover smear of light in a shape that often formed in the aftermath of a Minskytron display.

The variations were endless. By switching a few parameters you could turn the game into “hydraulic spacewar,” in which torpedoes flow out in ejaculatory streams instead of one by one. Or, as the night grew later and people became locked into interstellar mode, someone might shout, “Let’s turn on the Winds of Space!” and someone would hack up a warping factor, which would force players to make adjustments every time they moved. Though any improvement a hacker wished to make would be welcome, it was extremely bad form to make some weird change in the game unannounced. The effective social pressures that enforced the Hacker Ethic—which urged hands-on for improvement, not damage—prevented any instance of that kind of mischief. Anyway, the hackers were already engaged in a mind-boggling tweak of the system—they were using an expensive computer to play the world’s most glorified game!

Spacewar was played a hell of a lot. For some, it was addictive. Though no one could officially sign up the PDP-1 for a Spacewar session, the machine’s every free moment that spring seemed to have some version of the game running. Bottles of Coke in hand (and sometimes with money on the line), the hackers would run marathon tournaments. Russell eventually wrote a subroutine that would keep score, displaying in octal (everyone could sight-read that base-eight number system by then) the total of games won. For a while, the main drawback seemed to be that working the switches on the console of the PDP-1 was uncomfortable—everybody was getting sore elbows from keeping their arms at that particular angle. So one day Kotok and Saunders went over to the TMRC clubroom and found parts for what would become the first computer joysticks. Constructed totally with parts lying around the clubroom and thrown together in an hour of inspired construction, the control boxes were made of wood, with Masonite tops. They had switches for rotation and thrust, as well as a button for hyperspace. All controls were, of course, silent, so that you could surreptitiously circle around your opponent or duck into Nth space, should you care to.

In May 1962, at the annual MIT Open House, the hackers fed the paper tape with twenty-seven pages worth of PDP-1 assembly-language code into the machine, set up an extra display screen—actually a giant oscilloscope—and ran Spacewar all day to a public that drifted in and could not believe what they saw. The sight of it—a science-fiction game written by students and controlled by a computer—was so much on the verge of fantasy that no one dared predict that an entire genre of entertainment would eventually be spawned from it.

It wasn’t until years later, when Slug Russell was at Stanford University, that he realized that the game was anything but a hacker aberration. After working late one night, Russell and some friends went to a local bar that had some pinball machines. They played until closing time; then, instead of going home, Russell and his coworkers went back to their computer, and the first thing his friends did was run Spacewar. Suddenly it struck Russell: “These people just stopped playing a pinball machine and went to play Spacewar—by gosh, it is a pinball machine.” The most advanced, imaginative, expensive pinball machine the world had seen.

Like the hackers’ assemblers and the music program, Spacewar was not sold. Like any other program, it was placed in the drawer for anyone to access, look at, and rewrite as they saw fit. The group effort that stage by stage had improved the program could have stood for an argument for the Hacker Ethic: an urge to get inside the workings of the thing and make it better had led to measurable improvement. And of course it was all a huge amount of fun. It was no wonder that other PDP-1 owners began to hear about it, and the paper tapes holding Spacewar were freely distributed. At one point the thought crossed Slug Russell’s mind that maybe someone should be making money from this, but by then there were already dozens of copies circulating. DEC was delighted to get a copy, and the engineers there used it as a final diagnostic program on PDP-1s before they rolled them out the door. Then, without wiping the computer memory clean, they’d shut the machine off. The DEC sales force knew this, and often,when machines were delivered to new customers, the salesman would turn on the power, check to make sure no smoke was pouring out the back, and hit the “VY” location where Spacewar resided. And if the machine had been carefully packed and shipped, the heavy star would be in the center, and the cigarshaped rocket and the tube-shaped rocket would be ready for cosmic battle. A maiden flight for a magic machine.