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Authors: Michael Hiltzik

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This may seem complex at first. But in contrast to traditional languages,
object-oriented programming becomes relatively simpler as the data and
operations become more complex. The reason is that the underlying cal­culations always remain hidden within the object, never needing to be
explicitly invoked by the programmer. The object "John," for example,
needs only to be sent the message "+ Mary" to know that"+" in this con­text can mean only one thing: to append "Mary" to itself after a comma.

Although Kay drew the principles of what became known as "object-
oriented programming" from several well-known languages and com­puter systems, his system left many traditionally trained programmers
befuddled from the start. It was as if one tried to invent a new literary
language using conventional English words but devising radically new
rules of meaning. The individual words would look familiar, but the
way in which they related to each other in a sentence would seem
impenetrable—until the reader decoded the new rules, that is.

The CSL programmer Warren Teitelman, a world master of the lan­guage Lisp—a key source of Kays ideas

was one who found Smalltalk
perplexing at first. "People were used to thinking about programs in
terms of instructions and imperatives. If you thought in those terms you
had a lot of difficulty with Smalltalk. When you looked at it, your first
reaction was, OK, I sort of understand it, but where does the work get
done?"

Having been challenged by his teammates to define a language on a
page, Kay emerged after eight days of 4
a.m
. to 8
a.m
. struggle with a blue­print in hand for this new language with an unassuming name. Smalltalk
was compact enough to define itself in a page of code (although as it grew
more comprehensive, the pages got bigger and Kay’s handwriting more
minute). It was slow, because it placed an unusual workload on the com­puter. But it was astonishingly flexible.

Because anything could be an "object," whether numeral, word, fist, or
picture, Smalltalk lent itself especially well to representing graphic
images on a computer display. That became evident even in the days
before the Alto was ready. The Learning Research Group tested their
embryonic system on Novas equipped with their big, lumbering charac­ter generators and turned out new typefaces and half-tone bitmaps by
the score. Once the Alto came along, this process picked up speed as
Kay’s group enhanced Smalltalk with graphical capabilities that exceeded
anything else being developed at PARC.

In fact, Kay was so impatient to get his hands on the Alto that he did not
even wait for the first fully engineered models with printed circuit boards
to come off the production line set up in El Segundo, like the rest of the
labs. Instead he requisitioned six machines to be built with the same
clumsy and unreliable wire-wrapped circuitry used in the original two
prototypes, which he proceeded to install in the basement of Building 34.

The
idea was that he could get them
cheaper
and faster, even if they
turned
out to be flaky in operation and
hard to
maintain.
He
also ordered
these
first Altos with the low-end option
of only
96,000 bytes of memory,
rather than the maximum 128,000
bytes. The
first machines also came
with a 2.5-million byte, or 2.5-megabyte, storage disk.
(By
comparison,
todays household and office
PCs
often
come with
at least 32 or
64
million
bytes of memory and four to eight
billion
byte
storage disks.)

Under
this miserly configuration
Smalltalk
ran painfully slowly, in part
because the full-screen display
alone consumed
64,000
bytes,
leaving
almost
nothing for the program
kernel. By the
time
Kay
recognized that
he had engaged in a false economy
and tried
to scrounge a few high-
performance models out of turn,
the machines
were such a sought-after
sensation that no one would let
him cut in. "Forget
it, Alan," admonished
an amused Ed McCreight.
"You're the one
who screwed up."

But
once
Kay
finally got
all his machines
retrofitted with adequate
memory, Smalltalk fulfilled all
its developers'
expectations. While the
CSL
engineers busied
themselves with programs
to format the same
dull text-heavy documents as
fast as they
could make the Altos run, the
lunatic fringe worked the
machines' graphical
capabilities to the bone.
A
typical Learning Research
Group program
was no blob of black-on-
white text
but a carnival of drawings,
half-tone
photographs, even ani­mated pictures. "Objects mean
multimedia
documents," Kay would
say.
"You almost get them for free."

As
a result, the group's programs tended
to
favor the artist over the sci­entist.
An LRG
engineer named Bob
Shur
had programmed, with
Thacker's help, a musical synthesizer capability into the
Alto
that allowed
the machine to output twelve real-time
voices
at once, an astonishing
capability for a machine of the Altos
scale.
Then, in the fall of 1975, Ted Kaehler, although no musician himself,
developed
a
program called "Twang."
This
was a visual interface to a
number of music synthesizer programs that could capture, compose,
edit, and replay music on the Alto. Twang used a non-traditional notation,
black bars of differing lengths and locations to indicate differing tonic
and rhythmic values, that deliberately resembled the perforations on a
player piano roll. Twang was unusual in that it worked virtually in real
time. All previous computer music programs, including the pioneering
"FM" developed by John Chowning at Stanford, had to be compiled,
meaning that several hours of programming and debugging were neces­sary to produce a five-minute riff. That was unnecessary with Twang, with
which one could compose and program a polyphonic passage with as
many as eight voices almost as fast as one could hit the keys on an
attached piano keyboard.

While Merry, Ingalls, Kaehler, Tesler, and others engaged in the
grown-up activity of implementing serious Smalltalk tools on the Alto,
Kay decided to make good on his original claim that Smalltalk would be
a language simple enough for children to use. In the summer of 1973
he and Adele Goldberg assembled a group of eager preadolescents and
started teaching them how to program. The effort would shortly lead to
another of Kays painful run-ins with PARC management.

These were not average youngsters. Goldberg started with an
advanced class of seventh-graders at Palo Altos Jordan Road Middle
School, which served an upper-middle-class neighborhood a mile or so
from the Stanford campus. Once or twice a week the kids came up the
hill by bus or bicycle to Building 34, to be escorted to a roomful of Kay's
original wire-wrapped Altos down in the basement.

Goldberg loaded these with an inspired Smalltalk program she called
"A Box Named Joe." Joe, an outlined square, was a direct descendant of
Seymour Papert's LOGO turtle. With a series of one-fine commands the
seventh-graders could make it appear on the screen, turn on its side,
grow larger or smaller, or disappear. By arraying the commands in a
sequence, they achieved rudimentary animation.

The encounter was mutually enlightening. Although these young­sters had for the most part grown up in privileged and brainy homes,
they were surprised to come across grownups so guilelessly interested
in their burgeoning intellects.

"When you're a kid, adults either don't want you around, or when you
ask a question they give you a lecture," recalled Marian Goldeen, then
twelve, the daughter of a Palo Alto piano teacher and a businessman.

"But they
weren't like that.
Adele was pregnant,
but she looked a lot
younger than someone
I
thought would
be
working with computers."

The
scientists, some with
young families of
their own but few with
teenagers around the house,
found it
eye-opening to deal with twelve-
and
thirteen-year-olds who
grasped the basics
of programming instinc­tively.
One
weekend Goldeen,
who was an
honor student in mathemat­ics but had never programmed a
computer,
went home armed with a
few pointers from Goldberg and
coolly returned
with
a
full-blown
paint program, complete with a menu
of varied
shapes from which the
user could select a custom "brush."
Two older
students contrived pro­
grams
that wrote out musical scores
or drew
circuit diagrams, junior
versions of Twang and
SIL.

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