<s>
In	O
computer	B-Architecture
networking	I-Architecture
,	O
the	O
Name/Finger	O
protocol	O
and	O
the	O
Finger	O
user	O
information	O
protocol	O
are	O
simple	O
network	O
protocols	O
for	O
the	O
exchange	O
of	O
human-oriented	O
status	O
and	O
user	O
information	O
.	O
</s>
<s>
The	O
finger	O
program	O
was	O
written	O
in	O
1971	O
by	O
Les	O
Earnest	O
who	B-Application
created	O
the	O
program	O
to	O
solve	O
the	O
need	O
of	O
users	O
who	B-Application
wanted	O
information	O
on	O
other	O
users	O
of	O
the	O
network	O
.	O
</s>
<s>
Information	O
on	O
who	B-Application
is	O
logged	O
in	O
was	O
useful	O
to	O
check	O
the	O
availability	O
of	O
a	O
person	O
to	O
meet	O
.	O
</s>
<s>
This	O
was	O
probably	O
the	O
earliest	O
form	O
of	O
presence	B-Protocol
information	I-Protocol
for	O
remote	O
network	O
users	O
.	O
</s>
<s>
Prior	O
to	O
the	O
finger	O
program	O
,	O
the	O
only	O
way	O
to	O
get	O
this	O
information	O
was	O
with	O
a	O
who	B-Application
program	O
that	O
showed	O
IDs	O
and	O
terminal	O
line	O
numbers	O
(	O
the	O
server	B-Application
's	O
internal	O
number	O
of	O
the	O
communication	O
line	O
,	O
over	O
which	O
the	O
user	O
's	O
terminal	O
is	O
connected	O
)	O
for	O
logged-in	O
users	O
.	O
</s>
<s>
Earnest	O
named	O
his	O
program	O
after	O
the	O
idea	O
that	O
people	O
would	O
run	O
their	O
fingers	O
down	O
the	O
who	B-Application
list	O
to	O
find	O
what	O
they	O
were	O
looking	O
for	O
.	O
</s>
<s>
The	O
term	O
"	O
finger	O
"	O
has	O
a	O
definition	O
of	O
"	O
to	O
snitch	O
"	O
or	O
"	O
to	O
identify	O
"	O
:	O
this	O
made	O
"	O
finger	O
"	O
a	O
good	O
reminder/mnemonic	O
to	O
the	O
semantic	O
of	O
the	O
UNIX	B-Application
finger	O
command	O
(	O
a	O
client	B-Protocol
in	O
the	O
protocol	O
context	O
)	O
.	O
</s>
<s>
The	O
finger	O
daemon	B-Operating_System
runs	O
on	O
TCP	B-Protocol
port	I-Protocol
79	O
.	O
</s>
<s>
The	O
client	B-Protocol
will	O
(	O
in	O
the	O
case	O
of	O
remote	O
hosts	O
)	O
open	O
a	O
connection	O
to	O
port	O
79	O
.	O
</s>
<s>
Typically	O
the	O
server	B-Application
side	O
of	O
the	O
protocol	O
is	O
implemented	O
by	O
a	O
program	O
fingerd	O
or	O
in.fingerd	O
(	O
for	O
finger	O
daemon	B-Operating_System
)	O
,	O
while	O
the	O
client	B-Protocol
side	O
is	O
implemented	O
by	O
the	O
name	O
and	O
finger	O
programs	O
which	O
are	O
supposed	O
to	O
return	O
a	O
friendly	O
,	O
human-oriented	O
status	O
report	O
on	O
either	O
the	O
system	O
at	O
the	O
moment	O
or	O
a	O
particular	O
person	O
in	O
depth	O
.	O
</s>
<s>
There	O
is	O
no	O
required	O
format	O
,	O
and	O
the	O
protocol	O
consists	O
mostly	O
of	O
specifying	O
a	O
single	O
command	B-Application
line	I-Application
.	O
</s>
<s>
As	O
well	O
as	O
standard	O
user	O
information	O
,	O
finger	O
displays	O
the	O
contents	O
of	O
the	O
.project	O
and	O
.plan	O
files	O
in	O
the	O
user	O
's	O
home	B-Application
directory	I-Application
.	O
</s>
<s>
Often	O
this	O
file	O
(	O
maintained	O
by	O
the	O
user	O
)	O
contains	O
either	O
useful	O
information	O
about	O
the	O
user	O
's	O
current	O
activities	O
,	O
similar	O
to	O
micro-blogging	B-Application
,	O
or	O
alternatively	O
all	O
manner	O
of	O
humor	O
.	O
</s>
<s>
By	O
using	O
a	O
finger	O
client	B-Protocol
to	O
get	O
a	O
list	O
of	O
a	O
company	O
's	O
employee	O
names	O
,	O
email	O
addresses	O
,	O
phone	O
numbers	O
,	O
and	O
so	O
on	O
,	O
a	O
hacker	O
can	O
call	O
or	O
email	O
someone	O
at	O
a	O
company	O
requesting	O
information	O
while	O
posing	O
as	O
another	O
employee	O
.	O
</s>
<s>
The	O
finger	O
daemon	B-Operating_System
has	O
also	O
had	O
several	O
exploitable	O
security	O
holes	O
crackers	O
have	O
used	O
to	O
break	O
into	O
systems	O
.	O
</s>
<s>
It	O
is	O
implemented	O
on	O
Unix	B-Application
(	O
like	O
FreeBSD	B-Operating_System
and	O
macOS	B-Application
)	O
,	O
Unix-like	B-Operating_System
systems	I-Operating_System
(	O
like	O
Linux	B-Application
)	O
,	O
and	O
current	O
versions	O
of	O
Windows	B-Application
(	O
finger.exe	O
command	O
)	O
.	O
</s>
