<s>
A	O
sound	B-Application
server	I-Application
is	O
software	O
that	O
manages	O
the	O
use	O
of	O
and	O
access	O
to	O
audio	O
devices	O
(	O
usually	O
a	O
sound	B-Device
card	I-Device
)	O
.	O
</s>
<s>
It	O
commonly	O
runs	O
as	O
a	O
background	B-Operating_System
process	I-Operating_System
.	O
</s>
<s>
In	O
a	O
Unix-like	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
,	O
a	O
sound	B-Application
server	I-Application
mixes	O
different	O
data	O
streams	O
and	O
sends	O
out	O
a	O
single	O
unified	O
audio	O
to	O
an	O
output	O
device	O
.	O
</s>
<s>
The	O
mixing	O
is	O
usually	O
done	O
by	O
software	O
,	O
or	O
by	O
hardware	O
if	O
there	O
is	O
a	O
supported	O
sound	B-Device
card	I-Device
.	O
</s>
<s>
Sound	B-Application
server	I-Application
(	O
e.g.	O
</s>
<s>
Sound	B-Application
servers	I-Application
appeared	O
in	O
Unix-like	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
after	O
limitations	O
in	O
Open	B-Library
Sound	I-Library
System	I-Library
were	O
recognized	O
.	O
</s>
<s>
OSS	B-Library
is	O
a	O
basic	O
sound	O
interface	O
that	O
was	O
incapable	O
of	O
playing	O
multiple	O
streams	O
simultaneously	O
,	O
dealing	O
with	O
multiple	O
sound	B-Device
cards	I-Device
,	O
or	O
streaming	O
sound	O
over	O
the	O
network	O
.	O
</s>
<s>
A	O
sound	B-Application
server	I-Application
can	O
provide	O
these	O
features	O
by	O
running	O
as	O
a	O
daemon	B-Operating_System
.	O
</s>
<s>
With	O
a	O
sound	B-Application
server	I-Application
,	O
users	O
can	O
also	O
configure	O
global	O
and	O
per-application	O
sound	O
preferences	O
.	O
</s>
<s>
there	O
are	O
multiple	O
sound	B-Application
servers	I-Application
;	O
some	O
focus	O
on	O
providing	O
very	O
low	O
latency	O
,	O
while	O
others	O
concentrate	O
on	O
features	O
suitable	O
for	O
general	O
desktop	O
systems	O
.	O
</s>
<s>
While	O
diversification	O
allows	O
a	O
user	O
to	O
choose	O
just	O
the	O
features	O
that	O
are	O
important	O
to	O
a	O
particular	O
application	O
,	O
it	O
also	O
forces	O
developers	O
to	O
accommodate	O
these	O
options	O
by	O
necessitating	O
code	O
that	O
is	O
compatible	O
with	O
the	O
various	O
sound	B-Application
servers	I-Application
available	O
.	O
</s>
