<s>
Windows	B-Application
Template	I-Application
Library	I-Application
(	O
WTL	O
)	O
is	O
a	O
free	B-Application
software	I-Application
,	O
object-oriented	B-Language
C++	B-Language
template	O
library	B-Library
for	O
Win32	B-Library
development	O
.	O
</s>
<s>
WTL	O
was	O
created	O
by	O
Microsoft	O
employee	O
Nenad	O
Stefanovic	O
for	O
internal	O
use	O
and	O
later	O
released	O
as	O
an	O
unsupported	O
add-on	O
to	O
Visual	B-Application
Studio	I-Application
and	O
the	O
Win32	B-Library
Framework	O
SDK	B-Application
.	O
</s>
<s>
It	O
was	O
developed	O
primarily	O
as	O
a	O
light-weight	O
alternative	O
to	O
the	O
Microsoft	B-Language
Foundation	I-Language
Classes	I-Language
and	O
builds	O
upon	O
Microsoft	O
's	O
ATL	B-Language
,	O
another	O
lightweight	O
API	O
widely	O
used	O
to	O
create	O
COM	B-Application
and	O
ActiveX	B-Application
libraries	O
.	O
</s>
<s>
WTL	O
provides	O
support	O
for	O
implementing	O
various	O
user	O
interface	O
elements	O
,	O
from	O
frame	O
and	O
popup	O
windows	O
,	O
to	O
MDI	O
,	O
standard	O
and	O
common	O
controls	O
,	O
common	O
dialogs	O
,	O
property	O
sheets	O
and	O
pages	O
,	O
GDI	B-Operating_System
objects	O
,	O
and	O
other	O
common	O
UI	O
elements	O
,	O
such	O
as	O
scrollable	O
windows	O
,	O
splitter	O
windows	O
,	O
toolbars	O
and	O
command	O
bars	O
.	O
</s>
<s>
WTL	O
's	O
main	O
objective	O
is	O
to	O
deliver	O
small	O
and	O
efficient	O
code	O
,	O
close	O
in	O
size	O
and	O
speed	O
to	O
"	O
straight	O
"	O
SDK	B-Application
programs	O
while	O
providing	O
a	O
higher-level	O
and	O
more	O
flexible	O
object	O
model	O
to	O
developers	O
.	O
</s>
<s>
Most	O
of	O
the	O
WTL	O
API	O
is	O
a	O
mirror	O
of	O
the	O
standard	O
Win32	B-Library
calls	O
,	O
so	O
the	O
interface	O
tends	O
to	O
be	O
familiar	O
to	O
most	O
Windows	O
programmers	O
.	O
</s>
<s>
Although	O
no	O
official	O
documentation	O
from	O
Microsoft	O
exists	O
,	O
the	O
WTL	O
Documentation	O
Project	O
is	O
attempting	O
to	O
create	O
a	O
comprehensive	O
reference	O
for	O
the	O
library	B-Library
.	O
</s>
<s>
While	O
WTL	O
is	O
a	O
template	O
library	B-Library
and	O
therefore	O
code-based	O
,	O
the	O
original	O
license	O
was	O
similar	O
to	O
the	O
one	O
used	O
for	O
the	O
Microsoft	B-Language
Foundation	I-Language
Class	I-Language
Library	I-Language
(	O
MFC	O
)	O
source	O
code	O
,	O
although	O
it	O
contained	O
no	O
usage	O
or	O
distribution	O
restrictions	O
.	O
</s>
<s>
In	O
2004	O
Microsoft	O
made	O
the	O
complete	O
source	O
code	O
available	O
under	O
the	O
Common	O
Public	O
License	O
and	O
released	O
it	O
through	O
SourceForge	B-Application
.	O
</s>
<s>
Since	O
version	O
9.1	O
,	O
the	O
library	B-Library
is	O
licensed	O
under	O
the	O
Microsoft	B-License
Public	I-License
License	I-License
.	O
</s>
