<s>
The	O
GNU	B-Application
Free	I-Application
Documentation	I-Application
License	I-Application
(	O
GNU	B-Application
FDL	I-Application
or	O
simply	O
GFDL	B-Application
)	O
is	O
a	O
copyleft	B-License
license	I-License
for	O
free	O
documentation	O
,	O
designed	O
by	O
the	B-Operating_System
Free	I-Operating_System
Software	I-Operating_System
Foundation	I-Operating_System
(	O
FSF	O
)	O
for	O
the	B-Application
GNU	I-Application
Project	I-Application
.	O
</s>
<s>
It	O
is	O
similar	O
to	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
,	O
giving	O
readers	O
the	O
rights	O
to	O
copy	O
,	O
redistribute	O
,	O
and	O
modify	O
(	O
except	O
for	O
"	O
invariant	O
sections	O
"	O
)	O
a	O
work	O
and	O
requires	O
all	O
copies	O
and	O
derivatives	O
to	O
be	O
available	O
under	O
the	O
same	O
license	O
.	O
</s>
<s>
The	O
GFDL	B-Application
was	O
designed	O
for	O
manuals	O
,	O
textbooks	O
,	O
other	O
reference	O
and	O
instructional	O
materials	O
,	O
and	O
documentation	O
which	O
often	O
accompanies	O
GNU	B-Operating_System
software	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
free	O
online	O
encyclopedia	O
Wikipedia	O
uses	O
the	O
GFDL	B-Application
(	O
coupled	O
with	O
the	O
Creative	O
Commons	O
Attribution	O
Share-Alike	O
License	O
)	O
for	O
much	O
of	O
its	O
text	O
,	O
excluding	O
text	O
that	O
was	O
imported	O
from	O
other	O
sources	O
after	O
the	O
2009	O
licensing	O
update	O
that	O
is	O
only	O
available	O
under	O
the	O
Creative	O
Commons	O
license	O
.	O
</s>
<s>
The	O
GFDL	B-Application
was	O
released	O
in	O
draft	O
form	O
for	O
feedback	O
in	O
September	O
1999	O
.	O
</s>
<s>
The	O
first	O
discussion	O
draft	O
of	O
the	O
GNU	B-Application
Free	I-Application
Documentation	I-Application
License	I-Application
version	O
2	O
was	O
released	O
on	O
September	O
26	O
,	O
2006	O
,	O
along	O
with	O
a	O
draft	O
of	O
the	O
new	O
GNU	B-Application
Simpler	I-Application
Free	I-Application
Documentation	I-Application
License	I-Application
.	O
</s>
<s>
On	O
December	O
1	O
,	O
2007	O
,	O
Wikipedia	O
founder	O
Jimmy	O
Wales	O
announced	O
that	O
a	O
long	O
period	O
of	O
discussion	O
and	O
negotiation	O
between	O
and	O
amongst	O
the	B-Operating_System
Free	I-Operating_System
Software	I-Operating_System
Foundation	I-Operating_System
,	O
Creative	O
Commons	O
,	O
the	O
Wikimedia	O
Foundation	O
and	O
others	O
had	O
produced	O
a	O
proposal	O
supported	O
by	O
both	O
the	O
FSF	O
and	O
Creative	O
Commons	O
to	O
modify	O
the	O
Free	B-Application
Documentation	I-Application
License	I-Application
in	O
such	O
a	O
fashion	O
as	O
to	O
allow	O
the	O
possibility	O
for	O
the	O
Wikimedia	O
Foundation	O
to	O
migrate	O
the	O
projects	O
to	O
the	O
similar	O
Creative	O
Commons	O
Attribution	O
Share-Alike	O
(	O
CC	O
BY-SA	O
)	O
license	O
.	O
</s>
<s>
These	O
changes	O
were	O
implemented	O
on	O
version	O
1.3	O
of	O
the	O
license	O
,	O
which	O
includes	O
a	O
new	O
provision	O
allowing	O
certain	O
materials	O
released	O
under	O
the	O
(	O
GFDL	B-Application
)	O
license	O
to	O
be	O
used	O
under	O
a	O
Creative	O
Commons	O
Attribution	O
Share-Alike	O
license	O
also	O
.	O
</s>
<s>
While	O
the	O
Document	O
itself	O
is	O
wholly	O
editable	O
and	O
is	O
essentially	O
covered	O
by	O
a	O
license	O
equivalent	O
to	O
(	O
but	O
mutually	O
incompatible	O
with	O
)	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
,	O
some	O
of	O
the	O
secondary	O
sections	O
have	O
various	O
restrictions	O
designed	O
primarily	O
to	O
deal	O
with	O
proper	O
attribution	O
to	O
previous	O
authors	O
.	O
</s>
<s>
The	O
license	O
also	O
has	O
provisions	O
for	O
the	O
handling	O
of	O
front-cover	O
and	O
back-cover	B-Application
texts	I-Application
of	O
books	O
,	O
as	O
well	O
as	O
for	O
"	O
History	O
"	O
,	O
"	O
Acknowledgements	O
"	O
,	O
"	O
Dedications	O
"	O
and	O
"	O
Endorsements	O
"	O
sections	O
.	O
</s>
<s>
These	O
features	O
were	O
added	O
in	O
part	O
to	O
make	O
the	O
license	O
more	O
financially	O
attractive	O
to	O
commercial	O
publishers	O
of	O
software	O
documentation	O
,	O
some	O
of	O
whom	O
were	O
consulted	O
during	O
the	O
drafting	O
of	O
the	O
GFDL	B-Application
.	O
</s>
<s>
The	O
GFDL	B-Application
requires	O
the	O
ability	O
to	O
"	O
copy	O
and	O
distribute	O
the	O
Document	O
in	O
any	O
medium	O
,	O
either	O
commercially	O
or	O
noncommercially	O
"	O
and	O
therefore	O
is	O
incompatible	O
with	O
material	O
that	O
excludes	O
commercial	O
re-use	O
.	O
</s>
<s>
As	O
mentioned	O
above	O
,	O
the	O
GFDL	B-Application
was	O
designed	O
with	O
commercial	O
publishers	O
in	O
mind	O
,	O
as	O
Stallman	O
explained	O
:	O
Material	O
that	O
restricts	O
commercial	O
re-use	O
is	O
incompatible	O
with	O
the	O
license	O
and	O
cannot	O
be	O
incorporated	O
into	O
the	O
work	O
.	O
</s>
<s>
However	O
,	O
incorporating	O
such	O
restricted	O
material	O
may	O
be	O
fair	O
use	O
under	O
United	O
States	O
copyright	O
law	O
(	O
or	O
fair	O
dealing	O
in	O
some	O
other	O
countries	O
)	O
and	O
does	O
not	O
need	O
to	O
be	O
licensed	O
to	O
fall	O
within	O
the	O
GFDL	B-Application
if	O
such	O
fair	O
use	O
is	O
covered	O
by	O
all	O
potential	O
subsequent	O
uses	O
.	O
</s>
<s>
Although	O
the	O
two	O
licenses	O
work	O
on	O
similar	O
copyleft	B-License
principles	O
,	O
the	O
GFDL	B-Application
is	O
not	O
compatible	O
with	O
the	O
Creative	O
Commons	O
Attribution-ShareAlike	O
license	O
.	O
</s>
<s>
However	O
,	O
at	O
the	O
request	O
of	O
the	O
Wikimedia	O
Foundation	O
,	O
version	O
1.3	O
added	O
a	O
time-limited	O
section	O
allowing	O
specific	O
types	O
of	O
websites	O
using	O
the	O
GFDL	B-Application
to	O
additionally	O
offer	O
their	O
work	O
under	O
the	O
CC	O
BY-SA	O
license	O
.	O
</s>
<s>
These	O
exemptions	O
allow	O
a	O
GFDL-based	O
collaborative	O
project	O
with	O
multiple	O
authors	O
to	O
transition	O
to	O
the	O
CC	O
BY-SA	O
3.0	O
license	O
,	O
without	O
first	O
obtaining	O
the	O
permission	O
of	O
every	O
author	O
,	O
if	O
the	O
work	O
satisfies	O
several	O
conditions	O
:	O
</s>
<s>
The	O
work	O
must	O
have	O
been	O
produced	O
on	O
a	O
"	O
Massive	O
Multiauthor	O
Collaboration	O
Site	O
"	O
(	O
MMC	O
)	O
,	O
such	O
as	O
a	O
public	O
wiki	B-Protocol
for	O
example	O
.	O
</s>
<s>
If	O
external	O
content	O
originally	O
published	O
on	O
a	O
MMC	O
is	O
present	O
on	O
the	O
site	O
,	O
the	O
work	O
must	O
have	O
been	O
licensed	O
under	O
Version	O
1.3	O
of	O
the	O
GNU	B-Application
FDL	I-Application
,	O
or	O
an	O
earlier	O
version	O
but	O
with	O
the	O
"	O
or	O
any	O
later	O
version	O
"	O
declaration	O
,	O
with	O
no	O
cover	O
texts	O
or	O
invariant	O
sections	O
.	O
</s>
<s>
The	O
Wikimedia	O
Foundation	O
itself	O
after	O
a	O
public	O
referendum	O
,	O
invoked	O
this	O
process	O
to	O
dual-license	B-License
content	O
released	O
under	O
the	O
GFDL	B-Application
under	O
the	O
CC	O
BY-SA	O
license	O
in	O
June	O
2009	O
,	O
and	O
adopted	O
a	O
foundation-wide	O
attribution	O
policy	O
for	O
the	O
use	O
of	O
content	O
from	O
Wikimedia	O
Foundation	O
projects	O
.	O
</s>
<s>
There	O
have	O
currently	O
been	O
no	O
cases	O
involving	O
the	O
GFDL	B-Application
in	O
a	O
court	O
of	O
law	O
,	O
although	O
its	O
sister	O
license	O
for	O
software	O
,	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
,	O
has	O
been	O
successfully	O
enforced	O
in	O
such	O
a	O
setting	O
.	O
</s>
<s>
Although	O
the	O
content	O
of	O
Wikipedia	O
has	O
been	O
plagiarized	O
and	O
used	O
in	O
violation	O
of	O
the	O
GFDL	B-Application
by	O
other	O
sites	O
,	O
such	O
as	O
Baidu	O
Baike	O
,	O
no	O
contributors	O
have	O
ever	O
tried	O
to	O
bring	O
an	O
organization	O
to	O
court	O
due	O
to	O
violation	O
of	O
the	O
GFDL	B-Application
.	O
</s>
<s>
Some	O
critics	O
consider	O
the	O
GFDL	B-Application
a	O
non-free	O
license	O
.	O
</s>
<s>
Some	O
reasons	O
for	O
this	O
are	O
that	O
the	O
GFDL	B-Application
allows	O
"	O
invariant	O
"	O
text	O
which	O
cannot	O
be	O
modified	O
or	O
removed	O
,	O
and	O
that	O
its	O
prohibition	O
against	O
digital	O
rights	O
management	O
(	O
DRM	O
)	O
systems	O
applies	O
to	O
valid	O
usages	O
,	O
like	O
for	O
"	O
private	O
copies	O
made	O
and	O
not	O
distributed	O
"	O
.	O
</s>
<s>
Bruce	O
Perens	O
saw	O
the	O
GFDL	B-Application
even	O
outside	O
the	O
"	O
Free	B-Application
Software	I-Application
ethos	O
"	O
:	O
</s>
<s>
In	O
2006	O
,	O
Debian	O
developers	O
voted	O
to	O
consider	O
works	O
licensed	O
under	O
the	O
GFDL	B-Application
to	O
comply	O
with	O
their	O
Debian	B-License
Free	I-License
Software	I-License
Guidelines	I-License
provided	O
that	O
the	O
invariant	O
section	O
clauses	O
are	O
not	O
used	O
.	O
</s>
<s>
However	O
,	O
their	O
resolution	O
stated	O
that	O
even	O
without	O
invariant	O
sections	O
,	O
GFDL-licensed	O
software	O
documentation	O
"	O
is	O
still	O
not	O
free	O
of	O
trouble	O
"	O
,	O
namely	O
because	O
of	O
its	O
incompatibility	O
with	O
the	O
major	O
free	B-License
software	I-License
licenses	I-License
.	O
</s>
<s>
Those	O
opposed	O
to	O
the	O
GFDL	B-Application
have	O
recommended	O
the	O
use	O
of	O
alternative	O
licenses	O
such	O
as	O
the	O
BSD	B-Operating_System
License	I-Operating_System
or	O
the	O
GNU	B-License
GPL	I-License
.	O
</s>
<s>
The	O
FLOSS	B-Application
Manuals	I-Application
foundation	O
,	O
an	O
organization	O
devoted	O
to	O
creating	O
manuals	O
for	O
free	B-Application
software	I-Application
,	O
decided	O
to	O
eschew	O
the	O
GFDL	B-Application
in	O
favor	O
of	O
the	O
GPL	B-License
for	O
its	O
texts	O
in	O
2007	O
,	O
citing	O
the	O
incompatibility	O
between	O
the	O
two	O
,	O
difficulties	O
in	O
implementing	O
the	O
GFDL	B-Application
,	O
and	O
the	O
fact	O
that	O
the	O
GFDL	B-Application
"	O
does	O
not	O
allow	O
for	O
easy	O
duplication	O
and	O
modification	O
"	O
,	O
especially	O
for	O
digital	O
documentation	O
.	O
</s>
<s>
The	O
GNU	B-Application
FDL	I-Application
contains	O
the	O
statement	O
:	O
</s>
<s>
A	O
GNU	B-Application
FDL	I-Application
work	O
can	O
quickly	O
be	O
encumbered	O
because	O
a	O
new	O
,	O
different	O
title	O
must	O
be	O
given	O
and	O
a	O
list	O
of	O
previous	O
titles	O
must	O
be	O
kept	O
.	O
</s>
<s>
The	O
GNU	B-Application
FDL	I-Application
is	O
incompatible	O
in	O
both	O
directions	O
with	O
the	O
GPL	B-License
—	O
material	O
under	O
the	O
GNU	B-Application
FDL	I-Application
cannot	O
be	O
put	O
into	O
GPL	B-License
code	O
and	O
GPL	B-License
code	O
cannot	O
be	O
put	O
into	O
a	O
GNU	B-Application
FDL	I-Application
manual	O
.	O
</s>
<s>
At	O
the	O
June	O
22nd	O
and	O
23rd	O
2006	O
international	O
GPLv3	O
conference	O
in	O
Barcelona	O
,	O
Eben	O
Moglen	O
hinted	O
that	O
a	O
future	O
version	O
of	O
the	O
GPL	B-License
could	O
be	O
made	O
suitable	O
for	O
documentation	O
:	O
</s>
<s>
The	O
GNU	B-Application
FDL	I-Application
requires	O
that	O
licensees	O
,	O
when	O
printing	O
a	O
document	O
covered	O
by	O
the	O
license	O
,	O
must	O
also	O
include	O
"	O
this	O
License	O
,	O
the	O
copyright	O
notices	O
,	O
and	O
the	O
license	O
notice	O
saying	O
this	O
License	O
applies	O
to	O
the	O
Document	O
"	O
.	O
</s>
<s>
This	O
means	O
that	O
if	O
a	O
licensee	O
prints	O
out	O
a	O
copy	O
of	O
an	O
article	O
whose	O
text	O
is	O
covered	O
under	O
the	O
GNU	B-Application
FDL	I-Application
,	O
they	O
must	O
also	O
include	O
a	O
copyright	O
notice	O
and	O
a	O
physical	O
printout	O
of	O
the	O
GNU	B-Application
FDL	I-Application
,	O
which	O
is	O
a	O
significantly	O
large	O
document	O
in	O
itself	O
.	O
</s>
<s>
Wikivoyage	O
,	O
a	O
web	O
site	O
dedicated	O
to	O
free	O
content	O
travel	O
guides	O
,	O
chose	O
not	O
to	O
use	O
the	O
GFDL	B-Application
because	O
it	O
considers	O
it	O
unsuitable	O
for	O
short	O
printed	O
texts	O
.	O
</s>
<s>
Some	O
of	O
these	O
were	O
developed	O
independently	O
of	O
the	O
GNU	B-Application
FDL	I-Application
,	O
while	O
others	O
were	O
developed	O
in	O
response	O
to	O
perceived	O
flaws	O
in	O
the	O
GNU	B-Application
FDL	I-Application
.	O
</s>
<s>
Most	O
projects	O
of	O
the	O
Wikimedia	O
Foundation	O
,	O
including	O
Wikipedia	O
(	O
excluding	O
Wikivoyage	O
and	O
Wikinews	O
)	O
-	O
On	O
June	O
15	O
,	O
2009	O
,	O
the	O
Section	O
11	O
clauses	O
were	O
used	O
to	O
dual-license	B-License
the	O
content	O
of	O
these	O
wikis	B-Protocol
under	O
the	O
Creative	O
Commons	O
Attribution	O
Share-Alike	O
license	O
and	O
GFDL	B-Application
.	O
</s>
<s>
Citizendium	O
-	O
the	O
project	O
uses	O
GFDL	B-Application
for	O
articles	O
originally	O
from	O
Wikipedia	O
.	O
</s>
<s>
The	O
specification	O
documents	O
that	O
define	O
TRAK	B-Library
,	O
an	O
enterprise	B-Library
architecture	I-Library
framework	I-Library
,	O
are	O
released	O
under	O
the	O
GFDL	B-Application
.	O
</s>
