<s>
In	O
digital	B-Operating_System
file	I-Operating_System
management	O
,	O
copying	O
is	O
a	O
file	B-Operating_System
operation	O
that	O
creates	O
a	O
new	O
file	B-Operating_System
which	O
has	O
the	O
same	O
content	O
as	O
an	O
existing	O
file	B-Operating_System
.	O
</s>
<s>
Computer	B-General_Concept
operating	I-General_Concept
systems	I-General_Concept
include	O
file	B-Application
copying	I-Application
methods	O
to	O
users	O
,	O
with	O
operating	B-General_Concept
systems	I-General_Concept
with	O
graphical	B-Application
user	I-Application
interfaces	I-Application
(	O
GUIs	B-Application
)	O
often	O
providing	O
copy-and-paste	B-General_Concept
or	O
drag-and-drop	O
methods	O
of	O
file	B-Application
copying	I-Application
.	O
</s>
<s>
Operating	B-General_Concept
systems	I-General_Concept
may	O
have	O
specialized	O
file	B-Application
copying	I-Application
APIs	B-General_Concept
are	O
usually	O
able	O
to	O
tell	O
the	O
server	O
to	O
perform	O
the	O
copying	O
locally	O
,	O
without	O
sending	O
file	B-Operating_System
contents	O
over	O
the	O
network	O
,	O
thus	O
greatly	O
improving	O
performance	O
.	O
</s>
<s>
File	B-Application
copying	I-Application
is	O
the	O
creation	O
of	O
a	O
new	O
copy	B-Device
file	B-Operating_System
which	O
has	O
the	O
same	O
content	O
as	O
an	O
existing	O
file	B-Operating_System
.	O
</s>
<s>
There	O
are	O
several	O
different	O
technologies	O
that	O
use	O
the	O
term	O
shadowing	O
,	O
but	O
the	O
intent	O
of	O
shadowing	O
within	O
these	O
technologies	O
is	O
to	O
provide	O
an	O
exact	O
copy	B-Device
(	O
or	O
mirror	B-General_Concept
of	O
a	O
set	O
)	O
of	O
data	O
.	O
</s>
<s>
Depending	O
on	O
the	O
reasons	B-General_Concept
behind	O
the	O
shadow	O
operation	O
,	O
this	O
location	O
may	O
be	O
as	O
close	O
as	O
the	O
BIOS	O
chip	O
to	O
the	O
RAM	O
modules	O
,	O
a	O
second	O
harddrive	O
in	O
the	O
same	O
chassis	O
,	O
or	O
as	O
far	O
away	O
as	O
the	O
other	O
side	O
of	O
the	O
globe	O
.	O
</s>
<s>
All	O
computer	B-General_Concept
operating	I-General_Concept
systems	I-General_Concept
include	O
file	B-Application
copying	I-Application
provisions	O
in	O
the	O
user	O
interface	O
,	O
like	O
the	O
command	O
,	O
"	O
cp	B-Application
"	O
in	O
Unix	B-Application
and	O
"	O
COPY	B-Device
"	O
in	O
DOS	B-Device
;	O
operating	B-General_Concept
systems	I-General_Concept
with	O
a	O
graphical	B-Application
user	I-Application
interface	I-Application
,	O
or	O
GUI	B-Application
,	O
usually	O
provide	O
copy-and-paste	B-General_Concept
or	O
drag-and-drop	O
methods	O
of	O
file	B-Application
copying	I-Application
.	O
</s>
<s>
File	B-Application
manager	I-Application
applications	O
,	O
too	O
,	O
provide	O
an	O
easy	O
way	O
of	O
copying	B-Application
files	I-Application
.	O
</s>
<s>
Internally	O
,	O
however	O
,	O
while	O
some	O
systems	O
have	O
specialized	O
application	B-Application
programming	I-Application
interfaces	I-Application
(	O
APIs	B-General_Concept
)	O
for	O
copying	B-Application
files	I-Application
(	O
like	O
CopyFile	B-Application
and	O
CopyFileEx	B-Application
in	O
Windows	B-Library
API	I-Library
)	O
,	O
others	O
(	O
like	O
Unix	B-Application
and	O
DOS	B-Device
)	O
fall	O
back	O
to	O
simply	O
reading	O
the	O
contents	O
of	O
the	O
old	O
file	B-Operating_System
and	O
writing	O
it	O
to	O
the	O
new	O
file	B-Operating_System
.	O
</s>
<s>
This	O
makes	O
little	O
difference	O
with	O
local	O
files	O
(	O
those	O
on	O
the	O
computer	O
's	O
hard	O
drive	O
)	O
,	O
but	O
provides	O
an	O
interesting	O
situation	O
when	O
both	O
the	O
source	O
and	O
target	O
files	O
are	O
located	O
on	O
a	O
remote	O
file	B-Operating_System
server.Operating	O
systems	O
with	O
specialized	O
file	B-Application
copying	I-Application
APIs	B-General_Concept
are	O
usually	O
able	O
to	O
tell	O
the	O
server	O
to	O
perform	O
the	O
copying	O
locally	O
,	O
without	O
sending	O
file	B-Operating_System
contents	O
over	O
the	O
network	O
,	O
thus	O
greatly	O
improving	O
performance.Those	O
systems	O
that	O
have	O
no	O
comparable	O
APIs	B-General_Concept
,	O
however	O
,	O
have	O
to	O
read	O
the	O
file	B-Operating_System
contents	O
over	O
the	O
network	O
,	O
and	O
then	O
send	O
them	O
back	O
again	O
,	O
over	O
the	O
network	O
.	O
</s>
<s>
Sometimes	O
,	O
remote	O
file	B-Application
copying	I-Application
is	O
performed	O
with	O
a	O
specialized	O
command	O
,	O
like	O
"	O
NCOPY	O
"	O
in	O
DOS	B-Device
clients	O
for	O
Novell	B-Operating_System
NetWare	I-Operating_System
.	O
</s>
<s>
The	O
COPY	B-Device
command	O
in	O
some	O
versions	O
of	O
DR-DOS	B-Application
since	O
1992	O
,	O
has	O
built-in	O
support	O
for	O
this	O
.	O
</s>
<s>
An	O
even	O
more	O
complicated	O
situation	O
arises	O
when	O
one	O
needs	O
to	O
copy	B-Device
files	O
between	O
two	O
remote	O
servers	O
.	O
</s>
