<s>
Atari	B-Application
Program	I-Application
Exchange	I-Application
(	O
APX	O
)	O
was	O
a	O
division	O
of	O
Atari	O
,	O
Inc	O
.	O
that	O
sold	O
software	O
via	O
mail-order	O
for	O
the	O
Atari	B-Device
8-bit	I-Device
family	I-Device
of	O
home	O
computers	O
from	O
1981	O
until	O
1984	O
.	O
</s>
<s>
Quarterly	O
APX	O
catalogs	O
were	O
sent	O
to	O
all	O
registered	O
Atari	B-Device
8-bit	I-Device
owners	O
.	O
</s>
<s>
Several	O
APX	O
titles	O
,	O
such	O
as	O
Eastern	B-Application
Front	I-Application
(	O
1941	O
)	O
,	O
Caverns	B-Application
of	I-Application
Mars	I-Application
,	O
and	O
Atari	O
Star	O
winner	O
Typo	B-Application
Attack	I-Application
,	O
were	O
moved	O
to	O
Atari	O
's	O
official	O
product	O
line	O
.	O
</s>
<s>
A	O
few	O
internally	O
developed	O
Atari	O
products	O
were	O
sold	O
through	O
APX	O
,	O
such	O
as	O
Atari	B-Application
Pascal	I-Application
and	O
the	O
developer	O
handbook	O
De	O
Re	O
Atari	O
.	O
</s>
<s>
The	O
brainchild	O
of	O
Dale	O
Yocum	O
,	O
the	O
Atari	B-Application
Program	I-Application
Exchange	I-Application
started	O
in	O
February	O
1981	O
.	O
</s>
<s>
When	O
Atari	O
first	O
launched	O
the	O
Atari	B-Device
8-bit	I-Device
family	I-Device
in	O
late	O
1979	O
,	O
the	O
company	O
kept	O
most	O
of	O
the	O
hardware	O
details	O
secret	O
.	O
</s>
<s>
It	O
intended	O
to	O
be	O
the	O
primary	O
supplier	O
of	O
software	O
for	O
the	O
platform	O
,	O
as	O
had	O
been	O
the	O
case	O
with	O
the	O
Atari	B-General_Concept
Video	I-General_Concept
Computer	I-General_Concept
System	I-General_Concept
console	O
.	O
</s>
<s>
The	O
Antic	O
Software	O
catalog	O
was	O
bound	O
into	O
issues	O
of	O
the	O
magazine	O
and	O
later	O
included	O
Atari	B-Device
ST	I-Device
products	O
.	O
</s>
<s>
The	O
first	O
winner	O
was	O
the	O
educational	O
game	O
My	B-Application
First	I-Application
Alphabet	I-Application
by	O
Fernando	O
Herrera	O
.	O
</s>
<s>
He	O
used	O
the	O
money	O
to	O
cofound	O
video	O
game	O
developer	O
and	O
publisher	O
First	O
Star	O
Software	O
which	O
sold	O
several	O
of	O
his	O
games	O
,	O
including	O
Astro	B-Application
Chase	I-Application
and	O
Bristles	B-Application
.	O
</s>
<s>
The	O
1982	O
winner	O
was	O
Typo	B-Application
Attack	I-Application
by	O
David	O
Buehler	O
,	O
a	O
game	O
designed	O
to	O
improve	O
touch	O
typing	O
skill	O
.	O
</s>
<s>
Atari	O
published	O
it	O
as	O
a	O
cartridge	B-Protocol
in	O
1984	O
.	O
</s>
<s>
The	O
1983	O
winner	O
was	O
Getaway	B-Application
!	I-Application
</s>
<s>
Eastern	B-Application
Front	I-Application
(	O
1941	O
)	O
,	O
written	O
by	O
Chris	O
Crawford	O
,	O
was	O
the	O
Atari	B-Application
Program	I-Application
Exchange	I-Application
's	O
most	O
popular	O
program	O
.	O
</s>
<s>
The	O
source	O
code	O
for	O
Eastern	B-Application
Front	I-Application
,	O
and	O
a	O
scenario	O
editor	O
,	O
were	O
sold	O
separately	O
.	O
</s>
<s>
Eastern	B-Application
Front	I-Application
and	O
vertically-scrolling	O
shooter	O
Caverns	B-Application
of	I-Application
Mars	I-Application
were	O
both	O
converted	O
to	O
ROM	B-Protocol
cartridges	I-Protocol
and	O
became	O
part	O
of	O
the	O
official	O
Atari	O
product	O
line	O
.	O
</s>
<s>
One	O
of	O
Crawford	O
's	O
later	O
games	O
,	O
Excalibur	B-Application
,	O
was	O
also	O
sold	O
through	O
APX	O
.	O
</s>
<s>
John	O
Palevich	O
's	O
Dandy	B-Application
inspired	O
the	O
arcade	O
game	O
Gauntlet	B-Device
and	O
became	O
the	O
home	O
game	O
Dark	B-Application
Chambers	I-Application
.	O
</s>
<s>
Atari	O
distributed	O
two	O
licensed	O
arcade	O
ports	O
through	O
APX	O
:	O
1978	O
's	O
Avalanche	B-Application
,	O
credited	O
to	O
Dennis	O
Koble	O
who	O
wrote	O
the	O
original	O
arcade	O
game	O
,	O
and	O
1982	O
platform	O
game	O
Kangaroo	B-Application
,	O
which	O
was	O
uncredited	O
.	O
</s>
<s>
The	O
book	O
De	O
Re	O
Atari	O
:	O
A	O
Guide	O
to	O
Effective	O
Programming	O
(	O
1982	O
)	O
was	O
the	O
first	O
time	O
Atari	O
widely	O
published	O
information	O
about	O
the	O
internals	O
of	O
the	O
Atari	B-Device
8-bit	I-Device
computers	I-Device
.	O
</s>
<s>
Dunion	O
's	O
Debugging	O
tool	O
,	O
or	O
DDT	O
,	O
is	O
a	O
machine	O
language	O
debugger	O
which	O
was	O
later	O
incorporated	O
into	O
the	O
MAC/65	B-Application
assembler	O
from	O
Optimized	B-Operating_System
Systems	I-Operating_System
Software	I-Operating_System
.	O
</s>
<s>
The	O
Atari	B-Application
Pascal	I-Application
Language	I-Application
System	I-Application
is	O
a	O
version	O
of	O
the	O
Pascal	B-Application
programming	I-Application
language	I-Application
designed	O
for	O
an	O
unreleased	O
,	O
higher-spec	O
Atari	O
computer	O
model	O
.	O
</s>
<s>
It	O
was	O
relegated	O
to	O
the	O
Atari	B-Application
Program	I-Application
Exchange	I-Application
and	O
sold	O
without	O
support	O
.	O
</s>
<s>
Dandy	B-Application
author	O
Jack	O
Palevich	O
ported	O
to	O
Small-C	B-Language
to	O
the	O
Atari	B-Device
8-bit	I-Device
family	I-Device
which	O
was	O
published	O
by	O
APX	O
as	O
Deep	B-Application
Blue	I-Application
C	I-Application
.	O
The	O
source	O
code	O
was	O
sold	O
separately	O
as	O
Deep	O
Blue	O
Secrets	O
.	O
</s>
