<s>
In	O
computer	B-General_Concept
science	I-General_Concept
,	O
a	O
task	O
context	O
is	O
the	O
minimal	O
set	O
of	O
data	O
used	O
by	O
a	O
task	O
(	O
which	O
may	O
be	O
a	O
process	B-Operating_System
,	O
thread	B-Operating_System
,	O
or	O
fiber	B-Operating_System
)	O
that	O
must	O
be	O
saved	O
to	O
allow	O
a	O
task	O
to	O
be	O
interrupted	O
,	O
and	O
later	O
continued	O
from	O
the	O
same	O
point	O
.	O
</s>
<s>
The	O
concept	O
of	O
context	O
assumes	O
significance	O
in	O
the	O
case	O
of	O
interruptible	O
tasks	O
,	O
wherein	O
,	O
upon	O
being	O
interrupted	O
,	O
the	O
processor	O
saves	O
the	O
context	O
and	O
proceeds	O
to	O
serve	O
the	O
interrupt	B-General_Concept
service	I-General_Concept
routine	I-General_Concept
.	O
</s>
<s>
The	O
context	O
data	O
may	O
be	O
located	O
in	O
processor	B-General_Concept
registers	I-General_Concept
,	O
memory	O
used	O
by	O
the	O
task	O
,	O
or	O
in	O
control	B-Operating_System
registers	I-Operating_System
used	O
by	O
some	O
operating	B-General_Concept
systems	I-General_Concept
to	O
manage	O
the	O
task	O
.	O
</s>
<s>
The	O
storage	O
memory	O
(	O
files	O
used	O
by	O
a	O
task	O
)	O
is	O
not	O
concerned	O
by	O
the	O
"	O
task	O
context	O
"	O
in	O
the	O
case	O
of	O
a	O
context	B-Operating_System
switch	I-Operating_System
,	O
even	O
if	O
this	O
can	O
be	O
stored	O
for	O
some	O
uses	O
(	O
checkpointing	O
)	O
.	O
</s>
<s>
For	O
instance	O
,	O
if	O
an	O
array	O
is	O
needed	O
inside	O
a	O
structure	B-Language
,	O
it	O
can	O
be	O
added	O
to	O
it	O
since	O
version	O
2.0	O
,	O
but	O
only	O
in	O
an	O
unsafe/unsecure	O
context	O
.	O
</s>
<s>
The	O
keyword	O
prevents	O
the	O
garbage	B-General_Concept
collector	I-General_Concept
from	O
relocating	O
this	O
variable	O
.	O
</s>
