<s>
The	O
SHARE	B-Application
Operating	I-Application
System	I-Application
(	O
SOS	O
)	O
is	O
an	O
operating	O
system	O
introduced	O
in	O
1959	O
by	O
the	O
SHARE	O
user	O
group	O
.	O
</s>
<s>
It	O
is	O
an	O
improvement	O
on	O
the	O
General	B-Application
Motors	I-Application
GM-NAA	I-Application
I/O	I-Application
operating	O
system	O
,	O
the	O
first	O
operating	O
system	O
for	O
the	O
IBM	O
704	O
.	O
</s>
<s>
The	O
SHARE	B-Application
Operating	I-Application
System	I-Application
provided	O
new	O
methods	O
to	O
manage	O
buffers	B-General_Concept
and	O
input/output	B-General_Concept
devices	I-General_Concept
.	O
</s>
<s>
Like	O
GM-NAA	B-Application
I/O	I-Application
,	O
it	O
allowed	O
execution	O
of	O
programs	O
written	O
in	O
assembly	B-Language
language	I-Language
.	O
</s>
<s>
SOS	O
initially	O
ran	O
on	O
the	O
IBM	B-Device
709	I-Device
computer	O
and	O
was	O
then	O
ported	O
to	O
its	O
transistorized	O
successor	O
,	O
the	O
IBM	B-Device
7090	I-Device
.	O
</s>
<s>
In	O
1962	O
,	O
IBM	O
discontinued	O
support	O
for	O
SOS	O
and	O
announced	O
an	O
entirely	O
new	O
(	O
and	O
incompatible	O
)	O
operating	O
system	O
,	O
IBM	B-Operating_System
7090/94	I-Operating_System
IBSYS	I-Operating_System
.	O
</s>
