<s>
In	O
version	B-Architecture
control	I-Architecture
systems	I-Architecture
,	O
a	O
commit	O
is	O
an	O
operation	O
which	O
sends	O
the	O
latest	O
changes	O
of	O
the	O
source	O
code	O
to	O
the	O
repository	B-General_Concept
,	O
making	O
these	O
changes	O
part	O
of	O
the	O
head	O
revision	O
of	O
the	O
repository	B-General_Concept
.	O
</s>
<s>
Unlike	O
commits	B-Language
in	I-Language
data	I-Language
management	I-Language
,	O
commits	O
in	O
version	B-Architecture
control	I-Architecture
systems	I-Architecture
are	O
kept	O
in	O
the	O
repository	B-General_Concept
indefinitely	O
.	O
</s>
<s>
Thus	O
,	O
when	O
other	O
users	O
do	O
an	O
update	O
or	O
a	O
checkout	O
from	O
the	O
repository	B-General_Concept
,	O
they	O
will	O
receive	O
the	O
latest	O
committed	O
version	O
,	O
unless	O
they	O
specify	O
that	O
they	O
wish	O
to	O
retrieve	O
a	O
previous	O
version	O
of	O
the	O
source	O
code	O
in	O
the	O
repository	B-General_Concept
.	O
</s>
<s>
Version	B-Architecture
control	I-Architecture
systems	I-Architecture
allow	O
rolling	O
back	O
to	O
previous	O
versions	O
easily	O
.	O
</s>
<s>
In	O
this	O
context	O
,	O
a	O
commit	O
within	O
a	O
version	B-Architecture
control	I-Architecture
system	I-Architecture
is	O
protected	O
as	O
it	O
is	O
easily	O
rolled	O
back	O
,	O
even	O
after	O
the	O
commit	O
has	O
been	O
applied	O
.	O
</s>
<s>
To	O
commit	O
a	O
change	O
in	O
git	B-Application
on	O
the	O
command	B-Application
line	I-Application
,	O
assuming	O
git	B-Application
is	O
installed	O
,	O
the	O
following	O
command	O
is	O
run	O
:	O
</s>
<s>
git	B-Application
add	O
.	O
</s>
<s>
The	O
above	O
command	O
adds	O
all	O
of	O
the	O
files	O
in	O
the	O
working	O
directory	O
to	O
be	O
staged	O
for	O
the	O
git	B-Application
commit	O
.	O
</s>
<s>
After	O
the	O
commit	O
has	O
been	O
applied	O
,	O
the	O
last	O
step	O
is	O
to	O
push	O
the	O
commit	O
to	O
the	O
given	O
software	B-Application
repository	I-Application
,	O
in	O
the	O
case	O
below	O
named	O
origin	O
,	O
to	O
the	O
branch	O
master	O
:	O
</s>
<s>
To	O
commit	O
a	O
change	O
in	O
Mercurial	B-Protocol
on	O
the	O
command	B-Application
line	I-Application
,	O
assuming	O
hg	B-Protocol
is	O
installed	O
,	O
the	O
following	O
command	O
is	O
used	O
:	O
</s>
<s>
The	O
above	O
command	O
adds	O
all	O
of	O
the	O
files	O
in	O
the	O
working	O
directory	O
to	O
be	O
staged	O
for	O
the	O
Mercurial	B-Protocol
commit	O
.	O
</s>
<s>
After	O
the	O
commit	O
has	O
been	O
applied	O
,	O
the	O
last	O
step	O
is	O
to	O
push	O
the	O
commit	O
to	O
the	O
given	O
software	B-Application
repository	I-Application
,	O
to	O
the	O
default	O
branch	O
:	O
</s>
