<s>
In	O
a	O
non-interactive	B-General_Concept
computer	O
system	O
,	O
particularly	O
IBM	O
mainframes	B-Architecture
,	O
a	O
job	B-Application
stream	I-Application
,	O
jobstream	O
,	O
or	O
simply	O
job	B-General_Concept
is	O
the	O
sequence	O
of	O
job	B-Application
control	I-Application
language	I-Application
statements	O
(	O
JCL	O
)	O
and	O
data	O
(	O
called	O
instream	O
data	O
)	O
that	O
comprise	O
a	O
single	O
"	O
unit	O
of	O
work	O
for	O
an	O
operating	O
system	O
"	O
.	O
</s>
<s>
The	O
term	O
job	B-General_Concept
traditionally	O
means	O
a	O
one-off	O
piece	O
of	O
work	O
,	O
and	O
is	O
contrasted	O
with	O
a	O
batch	O
(	O
executing	B-General_Concept
the	O
same	O
steps	O
over	O
many	O
inputs	O
)	O
,	O
but	O
non-interactive	B-General_Concept
computation	O
has	O
come	O
to	O
be	O
called	O
"	O
batch	B-General_Concept
processing	I-General_Concept
"	O
,	O
and	O
thus	O
a	O
unit	O
of	O
batch	B-General_Concept
processing	I-General_Concept
is	O
often	O
called	O
a	O
job	B-General_Concept
,	O
or	O
by	O
the	O
oxymoronic	O
term	O
batch	B-General_Concept
job	I-General_Concept
;	O
see	O
job	B-General_Concept
for	O
details	O
.	O
</s>
<s>
Performing	O
a	O
job	B-General_Concept
consists	O
of	O
executing	B-General_Concept
one	O
or	O
more	O
programs	B-Application
.	O
</s>
<s>
Each	O
program	O
execution	O
,	O
called	O
a	O
job	B-General_Concept
step	O
,	O
jobstep	O
,	O
or	O
step	O
,	O
is	O
usually	O
related	O
in	O
some	O
way	O
to	O
the	O
others	O
in	O
the	O
job	B-General_Concept
.	O
</s>
<s>
Steps	O
in	O
a	O
job	B-General_Concept
are	O
executed	O
sequentially	O
,	O
possibly	O
depending	O
on	O
the	O
results	O
of	O
previous	O
steps	O
,	O
particularly	O
in	O
batch	B-General_Concept
processing	I-General_Concept
.	O
</s>
<s>
The	O
term	O
"	O
job	B-Application
stream	I-Application
"	O
is	O
particularly	O
associated	O
with	O
mainframes	B-Architecture
;	O
in	O
the	O
IBM	B-Application
z/OS	I-Application
operating	O
system	O
,	O
a	O
job	B-General_Concept
is	O
initiated	O
by	O
a	O
//	O
JOB	B-General_Concept
and	O
terminated	O
by	O
the	O
next	O
//	O
JOB	B-General_Concept
or	O
//	O
statement	O
.	O
</s>
<s>
Each	O
job	B-General_Concept
step	O
consists	O
of	O
one	O
//	O
EXEC	O
statement	O
indicating	O
the	O
program	O
to	O
be	O
executed	O
and	O
usually	O
multiple	O
//	O
DD	O
statements	O
defining	O
the	O
files	B-Operating_System
and	O
devices	O
to	O
be	O
used	O
.	O
</s>
<s>
A	O
simple	O
example	O
of	O
a	O
job	B-Application
stream	I-Application
is	O
a	O
system	O
to	O
print	O
payroll	O
checks	O
which	O
might	O
consist	O
of	O
the	O
following	O
steps	O
,	O
performed	O
on	O
a	O
batch	O
of	O
inputs	O
:	O
</s>
<s>
For	O
example	O
,	O
if	O
incorrect	O
data	O
is	O
input	O
to	O
the	O
first	O
step	O
the	O
job	B-General_Concept
might	O
terminate	O
without	O
executing	B-General_Concept
the	O
subsequent	O
steps	O
to	O
allow	O
the	O
payroll	O
department	O
to	O
correct	O
the	O
data	O
and	O
rerun	O
the	O
edit	O
.	O
</s>
<s>
If	O
there	O
are	O
no	O
errors	O
the	O
job	B-General_Concept
will	O
run	O
to	O
completion	O
with	O
no	O
manual	O
intervention	O
.	O
</s>
