<s>
|	O
released	O
=	O
2.0	O
(	O
4K	O
and	O
8K	O
editions	O
)	O
<ref>	O
,	O
Page	O
14	O
,	O
ALTAIR	B-Language
BASIC	I-Language
,	O
CLAIM	O
:	O
Not	O
just	O
anybody	O
's	O
BASIC	O
,	O
FACT	O
:	O
Not	O
just	O
anybody	O
's	O
BASIC	O
,	O
BY	O
:	O
KEITH	O
BRITTON	O
,	O
ROBERT	O
MULLEN	O
,	O
Altair	B-Language
BASIC	I-Language
version	O
2.0	O
had	O
a	O
serious	O
problem	O
in	O
that	O
a	O
jump	O
out	O
of	O
a	O
FOR	O
....	O
NEXT	O
loop	O
left	O
garbage	O
on	O
the	O
stack	O
.	O
</s>
<s>
Altair	B-Language
BASIC	I-Language
is	O
a	O
discontinued	O
interpreter	B-Application
for	O
the	O
BASIC	B-Language
programming	I-Language
language	I-Language
that	O
ran	O
on	O
the	O
MITS	B-Architecture
Altair	I-Architecture
8800	I-Architecture
and	O
subsequent	O
S-100	B-Architecture
bus	I-Architecture
computers	O
.	O
</s>
<s>
Altair	B-Language
BASIC	I-Language
was	O
the	O
start	O
of	O
the	O
Microsoft	B-Language
BASIC	I-Language
product	O
range	O
.	O
</s>
<s>
Gates	O
believed	O
that	O
,	O
by	O
providing	O
a	O
BASIC	O
interpreter	B-Application
for	O
the	O
new	O
computer	O
,	O
they	O
could	O
make	O
it	O
more	O
attractive	O
to	O
hobbyists	O
.	O
</s>
<s>
They	O
contacted	O
MITS	O
founder	O
Ed	O
Roberts	O
,	O
told	O
him	O
that	O
they	O
were	O
developing	O
an	O
interpreter	B-Application
,	O
and	O
asked	O
whether	O
he	O
would	O
like	O
to	O
see	O
a	O
demonstration	O
.	O
</s>
<s>
This	O
followed	O
the	O
questionable	O
engineering	O
industry	O
practice	O
of	O
a	O
trial	O
balloon	O
,	O
an	O
announcement	O
of	O
a	O
non-existent	B-Application
product	I-Application
to	O
gauge	O
interest	O
.	O
</s>
<s>
Gates	O
and	O
Allen	O
had	O
neither	O
an	O
interpreter	B-Application
nor	O
even	O
an	O
Altair	O
system	O
on	O
which	O
to	O
develop	O
and	O
test	O
one	O
.	O
</s>
<s>
However	O
,	O
Allen	O
had	O
written	O
an	O
Intel	B-General_Concept
8008	I-General_Concept
emulator	B-Application
for	O
their	O
previous	O
venture	O
,	O
Traf-O-Data	O
,	O
that	O
ran	O
on	O
a	O
PDP-10	B-Device
time-sharing	B-General_Concept
computer	O
.	O
</s>
<s>
Allen	O
adapted	O
this	O
emulator	B-Application
based	O
on	O
the	O
Altair	O
programmer	O
guide	O
,	O
and	O
they	O
developed	O
and	O
tested	O
the	O
interpreter	B-Application
on	O
Harvard	O
's	O
PDP-10	B-Device
.	O
</s>
<s>
Gates	O
and	O
Allen	O
bought	O
computer	O
time	O
from	O
a	O
timesharing	B-General_Concept
service	O
in	O
Boston	O
to	O
complete	O
their	O
BASIC	O
program	O
debugging	O
.	O
</s>
<s>
When	O
fellow	O
Harvard	O
student	O
Monte	O
Davidoff	O
stated	O
he	O
believed	O
the	O
system	O
should	O
use	O
floating-point	B-Algorithm
arithmetic	I-Algorithm
instead	O
of	O
the	O
integer	O
arithmetic	O
of	O
the	O
original	O
versions	O
,	O
and	O
claimed	O
he	O
could	O
write	O
such	O
a	O
system	O
that	O
could	O
still	O
fit	O
within	O
the	O
memory	O
limits	O
,	O
they	O
hired	O
Davidoff	O
to	O
write	O
the	O
package	O
.	O
</s>
<s>
The	O
finished	O
interpreter	B-Application
,	O
including	O
its	O
own	O
I/O	B-General_Concept
system	O
and	O
line	B-Application
editor	I-Application
,	O
fit	O
in	O
only	O
four	O
kilobytes	O
of	O
memory	O
,	O
leaving	O
plenty	O
of	O
room	O
for	O
the	O
interpreted	O
program	O
.	O
</s>
<s>
In	O
preparation	O
for	O
the	O
demo	O
,	O
they	O
stored	O
the	O
finished	O
interpreter	B-Application
on	O
a	O
punched	O
tape	O
that	O
the	O
Altair	O
could	O
read	O
,	O
and	O
Paul	O
Allen	O
flew	O
to	O
Albuquerque	O
.	O
</s>
<s>
Only	O
when	O
they	O
loaded	O
the	O
program	O
onto	O
an	O
Altair	O
and	O
saw	O
a	O
prompt	O
asking	O
for	O
the	O
system	O
's	O
memory	O
size	O
did	O
Gates	O
and	O
Allen	O
know	O
that	O
their	O
interpreter	B-Application
worked	O
on	O
the	O
Altair	O
hardware	O
.	O
</s>
<s>
Roberts	O
agreed	O
to	O
distribute	O
the	O
interpreter	B-Application
.	O
</s>
<s>
Extended	O
BASIC	O
added	O
PRINT	O
USING	O
and	O
basic	O
disk	O
commands	O
,	O
while	O
Disk	O
BASIC	O
further	O
extended	O
the	O
disk	O
commands	O
to	O
allow	O
raw	O
I/O	B-General_Concept
.	O
</s>
<s>
The	O
prices	O
were	O
discounted	O
to	O
,	O
,	O
and	O
respectively	O
for	O
those	O
who	O
purchased	O
"	O
8K	O
of	O
Altair	O
memory	O
,	O
and	O
an	O
Altair	O
I/O	B-General_Concept
board	O
"	O
.	O
</s>
<s>
Altair	B-Language
BASIC	I-Language
,	O
as	O
MITS	O
 '	O
preferred	O
BASIC	O
interpreter	B-Application
,	O
was	O
also	O
popular	O
.	O
</s>
<s>
However	O
,	O
the	O
hobbyists	O
took	O
a	O
"	O
share-alike	O
"	O
approach	O
to	O
software	O
and	O
thought	O
nothing	O
of	O
copying	O
the	O
BASIC	O
interpreter	B-Application
for	O
other	O
hobbyists	O
.	O
</s>
<s>
Homebrew	O
member	O
Dan	O
Sokol	O
was	O
especially	O
prolific	O
;	O
after	O
somehow	O
obtaining	O
a	O
pre-market	O
tape	O
of	O
the	O
interpreter	B-Application
,	O
he	O
made	O
25	O
copies	O
and	O
distributed	O
them	O
at	O
the	O
next	O
Homebrew	O
meeting	O
,	O
urging	O
recipients	O
to	O
make	O
more	O
copies	O
.	O
</s>
<s>
Under	O
the	O
terms	O
of	O
the	O
purchase	O
agreement	O
,	O
MITS	O
would	O
receive	O
the	O
rights	O
to	O
the	O
interpreter	B-Application
after	O
it	O
had	O
paid	O
a	O
certain	O
amount	O
in	O
royalties	O
.	O
</s>
<s>
However	O
,	O
Microsoft	O
had	O
developed	O
versions	O
of	O
the	O
interpreter	B-Application
for	O
other	O
systems	O
such	O
as	O
the	O
Motorola	B-Device
6800	I-Device
.	O
</s>
<s>
BASIC	O
interpreters	B-Application
remained	O
the	O
core	O
of	O
Microsoft	O
's	O
business	O
until	O
the	O
early	O
1980s	O
,	O
when	O
it	O
shifted	O
to	O
MS-DOS	B-Application
.	O
</s>
