<s>
In	O
computing	O
,	O
tree	O
is	O
a	O
recursive	O
directory	B-Application
listing	O
command	B-Application
or	O
program	B-Application
that	O
produces	O
a	O
depth-indented	O
listing	O
of	O
files	O
.	O
</s>
<s>
Originating	O
in	O
PC	O
-	O
and	O
MS-DOS	B-Application
,	O
it	O
is	O
found	O
in	O
Digital	B-Operating_System
Research	I-Operating_System
FlexOS	I-Operating_System
,	O
IBM/Toshiba	O
4690	B-Language
OS	I-Language
,	O
PTS-DOS	B-Operating_System
,	O
FreeDOS	B-Application
,	O
IBM	B-Application
OS/2	I-Application
,	O
Microsoft	B-Application
Windows	I-Application
,	O
and	O
ReactOS	B-Application
.	O
</s>
<s>
A	O
version	O
for	O
Unix	B-Application
and	O
Unix-like	B-Operating_System
systems	I-Operating_System
is	O
also	O
available	O
.	O
</s>
<s>
The	O
tree	B-Device
command	I-Device
is	O
frequently	O
used	O
as	O
part	O
of	O
a	O
technical	O
support	O
scam	O
,	O
where	O
the	O
command	B-Application
is	O
used	O
to	O
occupy	O
the	O
command	B-Application
prompt	O
screen	O
,	O
while	O
the	O
scammer	O
,	O
pretending	O
to	O
be	O
technical	O
support	O
,	O
types	O
additional	O
text	O
that	O
is	O
supposed	O
to	O
look	O
like	O
output	O
of	O
the	O
command	B-Application
.	O
</s>
<s>
With	O
no	O
arguments	O
,	O
tree	O
lists	O
the	O
files	O
in	O
the	O
current	B-Application
directory	I-Application
.	O
</s>
<s>
When	O
directory	B-Application
arguments	O
are	O
given	O
,	O
tree	O
lists	O
all	O
the	O
files	O
or	O
directories	B-Application
found	O
in	O
the	O
given	O
directories	B-Application
each	O
in	O
turn	O
.	O
</s>
<s>
Upon	O
completion	O
of	O
listing	O
all	O
files	O
and	O
directories	B-Application
found	O
,	O
tree	O
returns	O
the	O
total	O
number	O
of	O
files	O
and	O
directories	B-Application
listed	O
.	O
</s>
<s>
The	O
command	B-Application
is	O
available	O
in	O
MS-DOS	B-Application
versions	O
3.2	O
and	O
later	O
and	O
IBM	B-Operating_System
PC	I-Operating_System
DOS	I-Operating_System
releases	O
2	O
and	O
later	O
.	O
</s>
<s>
Digital	O
Research	O
DR	B-Application
DOS	I-Application
6.0	O
,	O
Itautec	O
SISNE	B-Operating_System
plus	I-Operating_System
,	O
and	O
Datalight	O
ROM-DOS	B-Operating_System
include	O
an	O
implementation	O
of	O
the	O
command	B-Application
.	O
</s>
<s>
The	O
Tree	B-Device
Command	I-Device
for	O
Linux	O
was	O
developed	O
by	O
Steve	O
Baker	O
.	O
</s>
<s>
The	O
FreeDOS	B-Application
version	O
was	O
developed	O
by	O
Dave	O
Dunfield	O
and	O
the	O
ReactOS	B-Application
version	O
was	O
developed	O
by	O
Asif	O
Bahrainwala	O
.	O
</s>
<s>
All	O
three	O
implementations	O
are	O
licensed	O
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
.	O
</s>
