<s>
In	O
computing	O
,	O
a	O
hidden	B-Application
folder	I-Application
(	O
sometimes	O
hidden	B-Application
directory	I-Application
)	O
or	O
hidden	B-Application
file	I-Application
is	O
a	O
folder	O
or	O
file	B-Operating_System
which	O
filesystem	B-Application
utilities	O
do	O
not	O
display	O
by	O
default	O
when	O
showing	O
a	O
directory	B-Application
listing	O
.	O
</s>
<s>
They	O
are	O
not	O
a	O
security	O
mechanism	O
because	O
access	O
is	O
not	O
restricted	O
–	O
usually	O
the	O
intent	O
is	O
simply	O
to	O
not	O
"	O
clutter	O
"	O
the	O
display	O
of	O
the	O
contents	O
of	O
a	O
directory	B-Application
listing	O
with	O
files	O
the	O
user	O
did	O
not	O
directly	O
create	O
.	O
</s>
<s>
In	O
Unix-like	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
,	O
any	O
file	B-Operating_System
or	O
folder	O
that	O
starts	O
with	O
a	O
dot	O
character	O
(	O
for	O
example	O
,	O
)	O
,	O
commonly	O
called	O
a	O
dot	B-Application
file	I-Application
or	O
dotfile	O
,	O
is	O
to	O
be	O
treated	O
as	O
hidden	O
–	O
that	O
is	O
,	O
the	O
ls	B-Application
command	O
does	O
not	O
display	O
them	O
unless	O
the	O
-a	O
or	O
-A	O
flags	O
(	O
ls	B-Application
-a	O
or	O
ls	B-Application
-A	O
)	O
are	O
used	O
.	O
</s>
<s>
In	O
most	O
command-line	B-Application
shells	O
,	O
wildcards	O
will	O
not	O
match	O
files	O
whose	O
names	O
start	O
with	O
.	O
</s>
<s>
A	O
convention	O
arose	O
of	O
using	O
dotfiles	B-Application
in	O
the	O
user	O
's	O
home	O
directory	B-Application
to	O
store	O
per-user	O
configuration	O
or	O
informational	O
text	O
.	O
</s>
<s>
Early	O
uses	O
of	O
this	O
were	O
the	O
well-known	O
dotfiles	B-Application
.profile	O
,	O
.login	O
,	O
and	O
.cshrc	O
,	O
which	O
are	O
configuration	O
files	O
for	O
the	B-Device
Bourne	I-Device
shell	I-Device
and	O
C	B-Operating_System
shell	I-Operating_System
and	O
shells	O
compatible	O
with	O
them	O
,	O
and	O
.plan	O
and	O
.project	O
,	O
both	O
used	O
by	O
the	O
finger	O
and	O
name	O
commands	O
.	O
</s>
<s>
Many	O
applications	O
,	O
from	O
bash	B-Operating_System
to	O
desktop	O
environments	O
such	O
as	O
GNOME	B-Application
,	O
now	O
store	O
their	O
per-user	O
configuration	O
this	O
way	O
,	O
but	O
the	O
Unix/Linux	O
freedesktop.org	B-Application
XDG	B-Application
Base	O
Directory	B-Application
Specification	O
aims	O
to	O
migrate	O
user	O
config	O
files	O
from	O
individual	O
dotfiles	B-Application
in	O
$HOME	O
to	O
non-hidden	O
files	O
in	O
the	O
hidden	B-Application
directory	I-Application
$	O
HOME/.config	O
.	O
</s>
<s>
The	O
Android	B-Application
operating	I-Application
system	I-Application
uses	O
empty	O
.nomedia	O
files	O
to	O
tell	O
smartphone	B-Application
apps	I-Application
not	O
to	O
display	O
or	O
include	O
the	O
contents	O
of	O
the	O
folder	O
.	O
</s>
<s>
This	O
prevents	O
digital	B-Application
photos	I-Application
and	O
digital	O
music	O
files	O
from	O
being	O
shown	O
in	O
picture	O
galleries	O
or	O
played	O
in	O
MP3	O
player	O
apps	B-Application
.	O
</s>
<s>
The	O
.nomedia	O
file	B-Operating_System
has	O
no	O
effect	O
on	O
the	O
filesystem	B-Application
or	O
even	O
the	O
operating	B-General_Concept
system	I-General_Concept
,	O
but	O
instead	O
depends	O
entirely	O
on	O
each	O
individual	O
app	O
to	O
respect	O
the	O
presence	O
of	O
the	O
different	O
files	O
.	O
</s>
<s>
In	O
the	O
GNOME	B-Application
desktop	I-Application
environment	I-Application
(	O
as	O
well	O
as	O
all	O
programs	O
written	O
using	O
GLib	B-Language
)	O
,	O
filenames	O
listed	O
in	O
a	O
file	B-Operating_System
named	O
.hidden	O
in	O
each	O
directory	B-Application
are	O
also	O
excluded	O
from	O
display	O
.	O
</s>
<s>
In	O
GNOME	B-Application
's	O
file	B-Operating_System
manager	O
,	O
the	O
keyboard	O
shortcut	O
+	O
enables	O
the	O
display	O
of	O
both	O
kinds	O
of	O
hidden	B-Application
files	I-Application
.	O
</s>
<s>
In	O
addition	O
to	O
the	O
"	O
dotfile	O
"	O
behaviour	O
,	O
files	O
with	O
the	O
"	O
Invisible	O
"	O
attribute	O
are	O
hidden	O
in	O
Finder	B-Application
,	O
although	O
not	O
in	O
ls	B-Application
.	O
</s>
<s>
The	O
"	O
Invisible	O
"	O
attribute	O
can	O
be	O
set	O
or	O
cleared	O
using	O
the	O
SetFile	O
command	O
;	O
for	O
example	O
,	O
invoking	O
SetFile	O
-a	O
V	O
jimbo	O
will	O
hide	O
the	O
file	B-Operating_System
jimbo	O
.	O
</s>
<s>
Starting	O
in	O
Mac	B-Device
OS	I-Device
X	I-Device
Snow	I-Device
Leopard	I-Device
,	O
the	O
chflags	B-Device
command	O
can	O
also	O
be	O
used	O
;	O
for	O
example	O
,	O
chflags	B-Device
hidden	O
jimbo	O
will	O
hide	O
the	O
file	B-Operating_System
jimbo	O
.	O
</s>
<s>
In	O
DOS	B-Device
systems	O
,	O
file	B-Application
directory	I-Application
entries	O
include	O
a	O
Hidden	B-Application
file	I-Application
attribute	O
which	O
is	O
manipulated	O
using	O
the	O
command	O
.	O
</s>
<s>
Using	O
the	O
command	B-Application
line	I-Application
command	O
dir	B-Application
/ah	O
displays	O
the	O
files	O
with	O
the	O
Hidden	O
attribute	O
.	O
</s>
<s>
In	O
addition	O
,	O
there	O
is	O
a	O
System	O
file	B-Application
attribute	I-Application
that	O
can	O
be	O
set	O
on	O
a	O
file	B-Operating_System
,	O
which	O
also	O
causes	O
the	O
file	B-Operating_System
to	O
be	O
hidden	O
in	O
directory	B-Application
listings	O
.	O
</s>
<s>
Use	O
the	O
command	B-Application
line	I-Application
command	O
dir	B-Application
/as	O
to	O
display	O
the	O
files	O
with	O
the	O
System	O
attribute	O
.	O
</s>
<s>
Under	O
Windows	B-Protocol
Explorer	I-Protocol
,	O
Hidden	B-Application
files	I-Application
and	I-Application
directories	I-Application
are	O
,	O
by	O
default	O
,	O
not	O
displayed	O
-	O
though	O
they	O
are	O
still	O
accessible	O
by	O
entering	O
the	O
full	O
path	O
into	O
the	O
explorer	O
address	O
bar	O
.	O
</s>
<s>
There	O
are	O
two	O
options	O
that	O
enable	O
the	O
display	O
of	O
hidden	B-Application
files	I-Application
.	O
</s>
<s>
The	O
main	O
'	O
Hidden	B-Application
files	I-Application
and	O
folders	O
 '	O
option	O
can	O
be	O
used	O
to	O
turn	O
on	O
the	O
display	O
of	O
hidden	B-Application
files	I-Application
but	O
this	O
wo	O
n't	O
,	O
on	O
its	O
own	O
,	O
display	O
hidden	O
system	O
files	O
.	O
</s>
<s>
A	O
second	O
option	O
,	O
'	O
Hide	O
protected	O
operating	B-General_Concept
system	I-General_Concept
files	O
 '	O
additionally	O
needs	O
to	O
be	O
turned	O
off	O
in	O
order	O
for	O
hidden	O
system	O
files	O
to	O
be	O
shown	O
.	O
</s>
<s>
Hidden	B-Application
files	I-Application
are	O
displayed	O
with	O
a	O
slight	O
transparency	O
,	O
so	O
even	O
when	O
they	O
are	O
visible	O
they	O
are	O
visually	O
delineated	O
from	O
non-hidden	O
files	O
.	O
</s>
<s>
Under	O
Windows	B-Protocol
Explorer	I-Protocol
,	O
the	O
content	O
of	O
a	O
directory	B-Application
can	O
also	O
be	O
hidden	O
just	O
by	O
appending	O
a	O
pre-defined	O
CLSID	O
to	O
the	O
end	O
of	O
the	O
folder	B-Application
name	I-Application
.	O
</s>
<s>
The	O
directory	B-Application
is	O
still	O
visible	O
,	O
but	O
its	O
content	O
becomes	O
one	O
of	O
the	O
Windows	O
Special	O
Folders	O
.	O
</s>
<s>
However	O
,	O
the	O
real	O
content	O
of	O
this	O
directory	B-Application
can	O
still	O
be	O
seen	O
using	O
the	O
CLI	O
command	O
dir	B-Application
.	O
</s>
