Hackers, Heroes of the Computer Revolution, by Steven Levy
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Steven Levy >> Hackers, Heroes of the Computer Revolution, by Steven Levy
In fact it was Jack Dennis who suggested to Samson that there
were considerable uses for the TX-O's ability 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 fourteenth bit in the eighteen-bit words the TX-0 had in its
accumulator in a given microsecond. The sound was on or off
depending on whether bit fourteen was a one or zero. 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 which yielded
complex arithmetical computations and statistical analyses.
These digits that Samson had jammed into the computer were a
universal language which could produce ANYTHING--a Bach fugue or
an anti-aircraft 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.
* * *
To hackers like Bob Saunders--balding, plump, and merry disciple
of the TX-0, president of TMRC's S&P group, student of systems--
it was a perfect existence. Saunders had grown up in the suburbs
of Chicago, and for as long as he could remember the workings of
electricity and telephone circuitry had fascinated him. Before
beginning MIT, Saunders had landed a dream summer job, working
for the phone company installing central office equipment, He
would spend eight blissful hours with soldering iron and pliers
in hand, working in the bowels of various systems, an idyll
broken by lunch hours spent in deep study of phone company
manuals. It was the phone company equipment underneath the TMRC
layout that had convinced Saunders to become active in the Model
Railroad Club.
Saunders, being an upperclassman, had come to the TX-0 later in
his college career than Kotok and Samson: he had used the
breathing space to actually lay the foundation for a social life,
which included courtship of and eventual marriage to Marge
French, who had done some non-hacking computer work for a
research project. Still, the TX-0 was the center of his college
career, and he shared the common hacker experience of seeing his
grades suffer from missed classes. It didn't bother him much,
because he knew that his real education was occurring in Room 240
of Building 26, behind the Tixo console. Years later he would
describe himself and the others as "an elite group. Other people
were off studying, spending their days up on four-floor buildings
making obnoxious vapors or off in the physics lab throwing
particles at things or whatever it is they do. And we were
simply not paying attention to what other folks were doing
because we had no interest in it. They were studying what they
were studying and we were studying what we were studying. And
the fact that much of it was not on the officially approved
curriculum was by and large immaterial."
The hackers came out at night. It was the only way to take full
advantage of the crucial "off-hours" of the TX-0. During the
day, Saunders would usually manage to make an appearance in a
class or two. Then some time spent performing "basic
maintenance"--things like eating and going to the bathroom. He
might see Marge for a while. But eventually he would filter over
to Building 26. He would go over some of the programs of the
night before, printed on the nine-and-a-half-inch-wide paper that
the Flexowriter used. He would annotate and modify the listing
to update the code to whatever he considered the next stage of
operation. Maybe then he would move over to the Model Railroad
Club, and he'd swap his program with someone, checking
simultaneously for good ideas and potential bugs. Then back to
Building 26, to the Kluge Room next to the TX-0, to find an
off-line Flexowriter on which to update his code. All the while
he'd be checking to see if someone had canceled a one-hour
session on the machine; his own session was scheduled at
something like two or three in the morning. He'd wait in the
Kluge Room, or play some bridge back at the Railroad Club, until
the time came.
Sitting at the console, facing the metal racks that held the
computer's transistors, each transistor representing a location
that either held or did not hold a bit of memory, Saunders would
set up the Flexowriter, which would greet him with the word
"WALRUS." This was something Samson had hacked, in honor of
Lewis Carroll's poem with the line "The time has come, the Walrus
said . . ." Saunders might chuckle at that as he went into the
drawer for the paper tape which held the assembler program and
fed that into the tape reader. Now the computer would be ready
to assemble his program, so he'd take the Flexowriter tape he'd
been working on and send that into the computer. He'd watch the
lights go on as the computer switched his code from "source" (the
symbolic assembly language) to "object" code (binary), which the
computer would punch out into another paper tape. Since that
tape was in the object code that the TX-0 understood, he'd feed
it in, hoping that the program would run magnificently.
There would most probably be a few fellow hackers kibitzing
behind him, laughing and joking and drinking Cokes and eating
some junk food they'd extracted from the machine downstairs.
Saunders preferred the lemon jelly wedges that the others called
"lemon gunkies." But at four in the morning, anything tasted
good. They would all watch as the program began to run, the
lights going on, the whine from the speaker humming in high or
low register depending on what was in Bit 14 in the accumulator,
and the first thing he'd see on the CRT display after the program
had been assembled and run was that the program had crashed. So
he'd reach into the drawer for the tape with the FLIT debugger
and feed THAT into the computer. The computer would then be a
debugging machine, and he'd send the program back in. Now he
could start trying to find out where things had gone wrong, and
maybe if he was lucky he'd find out, and change things by putting
in some commands by flicking some of the switches on the console
in precise order, or hammering in some code on the Flexowriter.
Once things got running--and it was always incredibly satisfying
when something worked, when he'd made that roomful of transistors
and wires and metal and electricity all meld together to create a
precise output that he'd devised--he'd try to add the next
advance to it. When the hour was over--someone already itching
to get on the machine after him--Saunders would be ready to spend
the next few hours figuring out what the heck had made the
program go belly-up.
The peak hour itself was tremendously intense, but during the
hours before, and even during the hours afterward, a hacker
attained a state of pure concentration. When you programmed a
computer, you had to be aware of where all the thousands of bits
of information were going from one instruction to the next, and
be able to predict--and exploit--the effect of all that movement.
When you had all that information glued to your cerebral being,
it was almost as if your own mind had merged into the environment
of the computer. Sometimes it took hours to build up to the
point where your thoughts could contain that total picture, and
when you did get to that point, it was such a shame to waste it
that you tried to sustain it by marathon bursts, alternatively
working on the computer or poring over the code that you wrote on
one of the off-line Flexowriters in the Kluge Room. You would
sustain that concentration by "wrapping around" to the next day.
Inevitably, that frame of mind spilled over to what random shards
of existence the hackers had outside of computing. The
knife-and-paintbrush contingent at TMRC were not pleased at all
by the infiltration of Tixo-mania into the club: they saw it as
a sort of Trojan horse for a switch in the club focus, from
railroading to computing. And if you attended one of the club
meetings held every Tuesday at five-fifteen, you could see the
concern: the hackers would exploit every possible thread of
parliamentary procedure to create a meeting as convoluted as the
programs they were hacking on the TX-0. Motions were made to
make motions to make motions, and objections ruled out of order
as if they were so many computer errors. A note in the minutes
of the meeting on November 24, 1959, suggests that "we frown on
certain members who would do the club a lot more good by doing
more S&P-ing and less reading Robert's Rules of Order." Samson
was one of the worst offenders, and at one point, an exasperated
TMRC member made a motion "to purchase a cork for Samson's oral
diarrhea."
Hacking parliamentary procedure was one thing, but the logical
mind-frame required for programming spilled over into more
commonplace activities. You could ask a hacker a question and
sense his mental accumulator processing bits until he came up
with a precise answer to the question you asked. Marge Saunders
would drive to the Safeway every Saturday morning in the
Volkswagen and upon her return ask her husband, "Would you like
to help me bring in the groceries?" Bob Saunders would reply,
"No." Stunned, Marge would drag in the groceries herself. After
the same thing occurred a few times, she exploded, hurling curses
at him and demanding to know why he said no to her question.
"That's a stupid question to ask," he said. "Of course I won't
LIKE to help you bring in the groceries. If you ask me if I'll
help you bring them in, that's another matter."
It was as if Marge had submitted a program into the TX-0, and the
program, as programs do when the syntax is improper, had crashed.
It was not until she debugged her question that Bob Saunders
would allow it to run successfully on his own mental computer.
CHAPTER 2
THE HACKER ETHIC
Something new was coalescing around the TX-0: a new way of life,
with a philosophy, an ethic, and a dream.
There was no one moment when it started to dawn on the TX-0
hackers that by devoting their technical abilities to computing
with a devotion rarely seen outside of monasteries they were the
vanguard of a daring symbiosis between man and machine. With a
fervor like that of young hot-rodders fixated on souping up
engines, they came to take their almost unique surroundings for
granted, Even as the elements of a culture were forming, as
legends began to accrue, as their mastery of programming started
to surpass any previous recorded levels of skill, the dozen or so
hackers were reluctant to acknowledge that their tiny society, on
intimate terms with the TX-0, had been slowly and implicitly
piecing together a body of concepts, beliefs, and mores.
The precepts of this revolutionary Hacker Ethic were not so much
debated and discussed as silently agreed upon. No manifestos
were issued. No missionaries tried to gather converts. The
computer did the converting, and those who seemed to follow the
Hacker Ethic most faithfully were people like Samson, Saunders,
and Kotok, whose lives before MIT seemed to be mere preludes to
that moment when they fulfilled themselves behind the console of
the TX-0. Later there would come hackers who took the implicit
Ethic even more seriously than the TX-0 hackers did, hackers like
the legendary Greenblatt or Gosper, though it would be some years
yet before the tenets of hackerism would be explicitly
delineated.
Still, even in the days of the TX-0, the planks of the platform
were in place. The Hacker Ethic:
ACCESS TO COMPUTERS--AND ANYTHING WHICH MIGHT TEACH YOU SOMETHING
ABOUT THE WAY THE WORLD WORKS--SHOULD BE UNLIMITED AND TOTAL.
ALWAYS YIELD TO THE HANDS-ON IMPERATIVE!
Hackers believe that essential lessons can be learned about the
systems--about the world--from taking things apart, seeing how
they work, and using this knowledge to create new and even more
interesting things. They resent any person, physical barrier, or
law that tries to keep them from doing this.
This is especially true when a hacker wants to fix something that
(from his point of view) is broken or needs improvement.
Imperfect systems infuriate hackers, whose primal instinct is to
debug them. This is one reason why hackers generally hate
driving cars--the system of randomly programmed red lights and
oddly laid out one-way streets causes delays which are so
goddamned UNNECESSARY that the impulse is to rearrange signs,
open up traffic-light control boxes . . .redesign the entire
system.
In a perfect hacker world, anyone pissed off enough to open up a
control box near a traffic light and take it apart to make it
work better should be perfectly welcome to make the attempt.
Rules which prevent you from taking matters like that into your
own hands are too ridiculous to even consider abiding by. This
attitude helped the Model Railroad Club start, on an extremely
informal basis, something called the Midnight Requisitioning
Committee. When TMRC needed a set of diodes, or some extra
relays, to build some new feature into The System, a few S&P
people would wait until dark and find their way into the places
where those things were kept. None of the hackers, who were as a
rule scrupulously honest in other matters, seemed to equate this
with "stealing." A willful blindness.
ALL INFORMATION SHOULD BE FREE.
If you don't have access to the information you need to improve
things, how can you fix them? A free exchange of information
particularly when the information was in the form of a computer
program, allowed for greater overall creativity. When you were
working on a machine like the TX-0, which came with almost no
software, everyone would furiously write systems programs to make
programming easier--Tools to Make Tools, kept in the drawer by
the console for easy access by anyone using the machine. This
prevented the dread, time-wasting ritual of reinventing the
wheel: instead of everybody writing his own version of the same
program, the best version would be available to everyone, and
everyone would be free to delve into the code and improve on
THAT. A world studded with feature-full programs, bummed to the
minimum, debugged to perfection.
The belief, sometimes taken unconditionally, that information
should be free was a direct tribute to the way a splendid
computer, or computer program, works--the binary bits moving in
the most straightforward, logical path necessary to do their
complex job, What was a computer but something which benefited
from a free flow of information? If, say, the accumulator found
itself unable to get information from the input/output (i/o)
devices like the tape reader or the switches, the whole system
would collapse. In the hacker viewpoint, any system could
benefit from that easy flow of information.
MISTRUST AUTHORITY--PROMOTE DECENTRALIZATION.
The best way to promote this free exchange of information is to
have an open system, something which presents no boundaries
between a hacker and a piece of information or an item of
equipment that he needs in his quest for knowledge, improvement,
and time on-line. The last thing you need is a bureaucracy.
Bureaucracies, whether corporate, government, or university, are
flawed systems, dangerous in that they cannot accommodate the
exploratory impulse of true hackers. Bureaucrats hide behind
arbitrary rules (as opposed to the logical algorithms by which
machines and computer programs operate): they invoke those rules
to consolidate power, and perceive the constructive impulse of
hackers as a threat.
The epitome of the bureaucratic world was to be found at a very
large company called International Business Machines--IBM. The
reason its computers were batch-processed Hulking Giants was only
partially because of vacuum tube technology, The real reason was
that IBM was a clumsy, hulking company which did not understand
the hacking impulse. If IBM had its way (so the TMRC hackers
thought), the world would be batch-processed, laid out on those
annoying little punch cards, and only the most privileged of
priests would be permitted to actually interact with the
computer.
All you had to do was look at someone in the IBM world, and note
the button-down white shirt, the neatly pinned black tie, the
hair carefully held in place, and the tray of punch cards in
hand. You could wander into the Computation Center, where the
704, the 709, and later the 7090 were stored--the best IBM had to
offer--and see the stifling orderliness, down to the roped-off
areas beyond which non-authorized people could not venture. And
you could compare that to the extremely informal atmosphere
around the TX-0, where grungy clothes were the norm and almost
anyone could wander in.
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 idea about the way a
computation center, and a world, should be run. Those people
could never understand the obvious superiority of a decentralized
system, with no one giving orders: a system where people could
follow their interests, and if along the way they discovered a
flaw in the system, they could embark on ambitious surgery. No
need to get a requisition form. just a need to get something
done.
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. These young adults who were
once outcasts found the computer a fantastic equalizer,
experiencing a feeling, according to Peter Samson, "like you
opened the door and walked through this grand new universe . . ."
Once they passed through that door and sat behind the console of
a million-dollar computer, hackers had power. So it was natural
to distrust any force which might try to limit the extent of that
power.
HACKERS SHOULD BE JUDGED BY THEIR HACKING, NOT BOGUS CRITERIA
SUCH AS DEGREES, AGE, RACE, OR POSITION.
The ready acceptance of twelve-year-old Peter Deutsch in the TX-0
community (though not by non-hacker graduate students) was a good
example. Likewise, people who trotted in with seemingly
impressive credentials were not taken seriously until they proved
themselves at the console of a computer. This meritocratic trait
was not necessarily rooted in the inherent goodness of hacker
hearts--it was mainly that hackers cared less about someone's
superficial characteristics than they did about his potential to
advance the general state of hacking, to create new programs to
admire, to talk about that new feature in the system.
YOU CAN CREATE ART AND BEAUTY ON A COMPUTER.
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 on-line speaker. The code of the program held a beauty
of its own. (Samson, though, was particularly obscure in
refusing to add comments to his source code explaining what he
was doing at a given time. One well-distributed program Samson
wrote went on for hundreds of assembly language instructions,
with only one comment beside an instruction which contained the
number 1750. The comment was RIPJSB, and people racked their
brains about its meaning until someone figured out that 1750 was
the year Bach died, and that Samson had written an abbreviation
for Rest In Peace Johann Sebastian Bach.)
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 which 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 when you didn't need speed or space much,
and you weren't thinking about art and beauty, you'd hack
together an ugly program, attacking the problem with "brute
force" methods. "Well, we can do this by adding twenty numbers,"
Samson might say to himself, "and it's quicker to write
instructions to do that than to think out a loop in the beginning
and the end to do the same job in seven or eight instructions."
But the latter program might be admired by fellow hackers, and
some programs were bummed to the fewest lines so artfully that
the author's peers would look at it and almost melt with awe.
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 which would save a whole block of instructions. (An
algorithm is a specific procedure which one can apply to solve a
complex computer problem; it is sort of a mathematical skeleton
key.) 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 techniques black-magic, visionary
quality which enabled them to discard the stale outlook of the
best minds on earth and come up with a totally unexpected new
algorithm.
This happened with the decimal print routine program. This was a
subroutines program within a program that you could sometimes
integrate into many different programs--to translate binary
numbers that the computer gave you into regular decimal numbers.
In Saunders' words, this problem became the "pawn's ass of
programming--if you could write a decimal print routine which
worked you knew enough about the computer to call yourself a
programmer of sorts." And if you wrote a GREAT decimal print
routine, you might be able to call yourself a hacker. More than
a competition, the ultimate bumming of the decimal print routine
became a sort of hacker Holy Grail.