<s>
DAC-1	B-Algorithm
,	O
for	O
Design	O
Augmented	O
by	O
Computer	O
,	O
was	O
one	O
of	O
the	O
earliest	O
graphical	O
computer	B-Application
aided	I-Application
design	I-Application
systems	O
.	O
</s>
<s>
GM	O
was	O
an	O
early	O
computer	O
user	O
,	O
using	O
punched	B-Architecture
card	I-Architecture
machines	O
as	O
early	O
as	O
1952	O
for	O
engineering	O
analysis	O
.	O
</s>
<s>
In	O
1956	O
,	O
together	O
with	O
North	O
American	O
Aviation	O
,	O
they	O
developed	O
the	O
first	O
"	O
official	O
"	O
batch	B-General_Concept
processing	I-General_Concept
operating	B-General_Concept
system	I-General_Concept
for	O
IBM	O
systems	O
,	O
GM-NAA	B-Application
I/O	I-Application
.	O
</s>
<s>
In	O
1958	O
they	O
were	O
one	O
of	O
the	O
earliest	O
users	O
of	O
IBM	O
's	O
new	O
FORTRAN	B-Application
compiler	O
.	O
</s>
<s>
Lookups	O
would	O
be	O
handled	O
via	O
punched	B-Architecture
card	I-Architecture
queries	O
,	O
which	O
would	O
allow	O
operators	O
to	O
quickly	O
retrieve	O
documents	O
for	O
manipulation	O
into	O
whatever	O
local	O
format	O
the	O
user	O
needed	O
,	O
and	O
then	O
print	O
it	O
.	O
</s>
<s>
The	O
Data	O
Processing	O
department	O
had	O
already	O
been	O
experimenting	O
with	O
an	O
IBM	B-Device
704	I-Device
computer	O
displaying	O
points	O
on	O
the	O
IBM	O
780	O
display	O
which	O
were	O
recorded	O
to	O
8mm	O
film	O
.	O
</s>
<s>
However	O
,	O
the	O
displays	O
were	O
not	O
based	O
on	O
storage	B-General_Concept
tubes	I-General_Concept
,	O
so	O
the	O
images	O
disappeared	O
shortly	O
after	O
they	O
were	O
drawn	O
.	O
</s>
<s>
Although	O
it	O
was	O
suitable	O
for	O
demonstration	O
purposes	O
,	O
a	O
real-world	O
system	O
would	O
need	O
additional	O
hardware	O
to	O
offload	O
this	O
task	O
from	O
the	O
CPU	B-General_Concept
.	O
</s>
<s>
In	O
order	O
to	O
avoid	O
confusion	O
over	O
the	O
term	O
"	O
digital	O
"	O
,	O
which	O
at	O
that	O
time	O
was	O
most	O
closely	O
associated	O
with	O
fingers	O
and	O
not	O
computing	O
,	O
the	O
name	O
changed	O
to	O
DAC-1	B-Algorithm
.	O
</s>
<s>
In	O
August	O
,	O
the	O
team	O
was	O
given	O
the	O
go-ahead	O
to	O
start	O
work	O
with	O
IBM	O
to	O
purchase	O
an	O
IBM	B-Device
7090	I-Device
computer	O
and	O
develop	O
commercial	O
versions	O
of	O
the	O
display	O
hardware	O
.	O
</s>
<s>
Once	O
converted	O
,	O
the	O
diagrams	O
could	O
be	O
output	O
into	O
the	O
APT	B-Language
numerical	O
control	O
language	O
for	O
direct	O
output	O
on	O
milling	O
machines	O
.	O
</s>
<s>
The	O
system	O
was	O
hosted	O
by	O
the	O
7090	O
,	O
IBM	O
's	O
then-standard	O
large	O
business	O
offering	O
,	O
partnered	O
with	O
two	O
new	O
channel	B-Device
controllers	I-Device
for	O
the	O
yet-to-be-released	O
IBM	B-Device
1301	I-Device
hard	B-Device
disk	I-Device
system	O
,	O
and	O
a	O
custom	O
controller	O
to	O
drive	O
multiple	O
graphical	O
terminals	O
.	O
</s>
<s>
The	O
production	O
DAC-1	B-Algorithm
system	O
went	O
live	O
in	O
Warren	O
in	O
April	O
1963	O
.	O
</s>
<s>
At	O
the	O
time	O
the	O
1301	O
was	O
not	O
ready	O
,	O
so	O
an	O
IBM	B-Device
1401	I-Device
and	O
IBM	B-Device
1405	I-Device
were	O
used	O
instead	O
.	O
</s>
<s>
DAC-1	B-Algorithm
was	O
one	O
of	O
the	O
earliest	O
production	O
CAD	B-Application
systems	O
to	O
enter	O
use	O
,	O
only	O
the	O
Itek	O
built	O
Digigraphics	B-Algorithm
system	O
beat	O
it	O
,	O
albeit	O
to	O
the	O
extent	O
of	O
a	O
single	O
machine	O
before	O
it	O
was	O
taken	O
over	O
by	O
Control	O
Data	O
Corporation	O
.	O
</s>
<s>
In	O
November	O
1963	O
,	O
DAC-1	B-Algorithm
was	O
used	O
to	O
create	O
a	O
model	O
of	O
a	O
trunk	O
lid	O
in	O
a	O
straight-through	O
manner	O
.	O
</s>
<s>
With	O
the	O
successful	O
delivery	O
of	O
DAC-1	B-Algorithm
,	O
IBM	O
turned	O
to	O
commercializing	O
the	O
system	O
in	O
"	O
Project	O
Alpine	O
"	O
.	O
</s>
<s>
The	O
results	O
of	O
Alpine	O
were	O
the	O
IBM	B-Device
2250	I-Device
graphics	O
terminal	O
,	O
2280	O
film	O
recorder	O
and	O
2281	O
film	O
scanner	O
.	O
</s>
<s>
Unlike	O
the	O
DAC-1	B-Algorithm
'	O
s	O
7090	O
,	O
the	O
Alpine	O
products	O
were	O
all	O
aimed	O
for	O
use	O
with	O
the	O
newly	O
announced	O
IBM	B-Application
360	I-Application
series	O
of	O
computers	O
.	O
</s>
<s>
The	O
graphics	O
terminal	O
was	O
quite	O
successful	O
and	O
IBM	O
became	O
a	O
major	O
CAD	B-Application
vendor	O
.	O
</s>
<s>
In	O
1967	O
the	O
CAD	B-Application
project	O
was	O
officially	O
ended	O
.	O
</s>
<s>
By	O
this	O
point	O
IBM	O
had	O
long	O
abandoned	O
the	O
7090	O
series	O
for	O
the	O
360	O
,	O
and	O
was	O
already	O
working	O
on	O
its	O
replacement	O
,	O
the	O
IBM	B-Device
System/370	I-Device
.	O
</s>
<s>
When	O
polled	O
,	O
team	O
leaders	O
within	O
the	O
project	O
universally	O
pointed	O
to	O
the	O
batch-oriented	B-General_Concept
operating	B-General_Concept
system	I-General_Concept
as	O
the	O
primary	O
impediment	O
to	O
a	O
truly	O
interactive	O
design	O
system	O
,	O
with	O
computer	O
performance	O
and	O
a	O
hierarchical	B-Application
file	I-Application
system	I-Application
as	O
secondary	O
concerns	O
.	O
</s>
<s>
This	O
led	O
to	O
the	O
MCTS	O
system	O
,	O
"	O
Multiple	B-General_Concept
Console	I-General_Concept
Time	I-General_Concept
Sharing	I-General_Concept
System	I-General_Concept
"	O
,	O
a	O
version	O
of	O
Multics	B-Application
adapted	O
for	O
their	O
own	O
use	O
,	O
which	O
they	O
developed	O
on	O
the	O
CDC	B-Device
STAR-100	I-Device
computer	O
.	O
</s>
<s>
The	O
DAC-1	B-Algorithm
system	O
included	O
its	O
own	O
custom	O
operating	B-General_Concept
system	I-General_Concept
,	O
known	O
,	O
as	O
was	O
typical	O
at	O
the	O
time	O
,	O
simply	O
as	O
"	O
monitor	O
"	O
.	O
</s>
<s>
Monitor	O
was	O
based	O
on	O
the	O
earlier	O
batch	B-General_Concept
processing	I-General_Concept
systems	O
developed	O
at	O
GM	O
and	O
IBM	O
,	O
but	O
fed	O
in	O
the	O
batches	O
not	O
from	O
punched	B-Architecture
cards	I-Architecture
,	O
but	O
from	O
the	O
attached	O
channel	B-Device
controllers	I-Device
instead	O
.	O
</s>
<s>
Although	O
the	O
term	O
was	O
not	O
in	O
widespread	O
use	O
at	O
the	O
time	O
,	O
the	O
DAC-1	B-Algorithm
system	O
was	O
thus	O
an	O
early	O
example	O
of	O
a	O
time-sharing	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
Unlike	O
traditional	O
batch	B-General_Concept
systems	I-General_Concept
,	O
where	O
operators	O
manually	O
scheduled	O
workflows	O
for	O
fastest	O
possible	O
access	O
to	O
resources	O
,	O
DAC-1	B-Algorithm
'	O
s	O
workload	O
would	O
be	O
unpredictable	O
.	O
</s>
<s>
In	O
order	O
to	O
improve	O
performance	O
,	O
the	O
DAC-1	B-Algorithm
software	O
was	O
left	O
in	O
the	O
core	O
,	O
isolated	O
in	O
one	O
of	O
two	O
16kbyte	O
logical	O
banks	O
.	O
</s>
<s>
After	O
the	O
DAC-1	B-Algorithm
was	O
first	O
installed	O
,	O
the	O
original	O
7090	O
was	O
relegated	O
to	O
other	O
tasks	O
and	O
was	O
replaced	O
by	O
an	O
IBM	O
7094-II	O
.	O
</s>
<s>
In	O
addition	O
to	O
being	O
faster	O
,	O
this	O
machine	O
was	O
equipped	O
with	O
two	O
32kbyte	O
core	B-General_Concept
memory	I-General_Concept
stores	O
,	O
an	O
unusual	O
arrangement	O
.	O
</s>
<s>
Programming	O
on	O
the	O
DAC	O
system	O
was	O
in	O
IBM	O
's	O
FORTRAN	B-Application
IV	O
compiler	O
,	O
but	O
it	O
quickly	O
became	O
clear	O
that	O
a	O
language	O
with	O
graphics	O
primitives	O
would	O
be	O
highly	O
desirable	O
.	O
</s>
<s>
GM	O
started	O
with	O
an	O
existing	O
ALGOL	B-Language
58	I-Language
derivative	O
from	O
the	O
University	O
of	O
Michigan	O
,	O
MAD	O
(	O
Michigan	O
Algorithm	O
Decoder	O
)	O
,	O
adding	O
to	O
it	O
and	O
creating	O
their	O
own	O
version	O
,	O
NOMAD	O
.	O
</s>
<s>
A	O
similar	O
language	O
was	O
also	O
developed	O
for	O
the	O
special	O
task	O
of	O
running	O
on	O
the	O
channel	B-Device
controllers	I-Device
.	O
</s>
<s>
The	O
DAC-1	B-Algorithm
system	O
also	O
included	O
a	O
custom	O
language	O
intended	O
for	O
the	O
users	O
,	O
not	O
the	O
programmers	O
.	O
</s>
<s>
DGL	O
,	O
for	O
descriptive	O
geometry	O
language	O
"	O
was	O
a	O
simple	O
domain-specific	B-Language
language	I-Language
that	O
contained	O
a	O
number	O
of	O
basic	O
geometrical	O
operators	O
and	O
variable	O
assignment	O
.	O
</s>
<s>
Users	O
could	O
write	O
programs	O
in	O
DGL	O
and	O
input	O
them	O
into	O
DAC	O
using	O
punched	B-Architecture
cards	I-Architecture
.	O
</s>
<s>
The	O
IBM	O
design	O
used	O
a	O
capacitance	B-Device
screen	I-Device
with	O
a	O
metal	O
pencil	O
for	O
input	O
,	O
providing	O
a	O
directly	O
read	O
X	O
and	O
Y	O
coordinate	O
.	O
</s>
<s>
The	O
basic	O
system	O
was	O
similar	O
to	O
modern	O
touch	B-Device
screen	I-Device
systems	O
like	O
the	O
iPhone	B-Device
,	O
but	O
not	O
sensitive	O
enough	O
to	O
detect	O
a	O
finger	O
and	O
instead	O
required	O
a	O
wired	O
conductor	O
to	O
complete	O
the	O
circuit	O
.	O
</s>
<s>
The	O
GM	O
team	O
later	O
visited	O
Douglas	O
Engelbart	O
's	O
lab	O
where	O
they	O
saw	O
the	B-Device
first	I-Device
computer	I-Device
mouse	I-Device
,	O
and	O
based	O
future	O
projects	O
on	O
this	O
device	O
instead	O
.	O
</s>
