<s>
qooxdoo	B-Language
is	O
an	O
open-source	B-Application
Ajax	B-General_Concept
web	B-Application
application	I-Application
framework	I-Application
.	O
</s>
<s>
It	O
is	O
an	O
LGPL	B-Application
-	O
and/or	O
EPL-licensed	O
client-side	O
and	O
server-agnostic	O
solution	O
,	O
and	O
includes	O
support	O
for	O
professional	O
JavaScript	B-Language
development	O
,	O
a	O
graphical	B-Application
user	I-Application
interface	I-Application
(	O
GUI	B-Application
)	O
toolkit	B-Library
and	O
high-level	O
client-server	O
communication	O
.	O
</s>
<s>
qooxdoo	B-Language
is	O
entirely	O
class-based	O
,	O
tries	O
to	O
leverage	O
the	O
features	O
of	O
object-oriented	B-Language
JavaScript	B-Language
and	O
is	O
based	O
on	O
namespaces	O
.	O
</s>
<s>
Most	O
modern	O
browsers	O
are	O
supported	O
,	O
including	O
Gecko	B-Language
(	O
Firefox	B-Application
,	O
Mozilla	B-Operating_System
,	O
SeaMonkey	B-Language
)	O
,	O
Presto	B-Application
(	O
Opera	B-Application
)	O
,	O
Trident	B-Application
(	O
Internet	B-Application
Explorer	I-Application
,	O
RealPlayer	B-Application
,	O
Winamp	B-Application
)	O
,	O
WebKit	B-Language
(	O
Chrome	B-Application
,	O
Safari	B-Application
)	O
.	O
</s>
<s>
It	O
includes	O
an	O
API	O
reference	O
that	O
is	O
auto-generated	O
from	O
Javadoc-like	O
comments	O
.	O
</s>
<s>
Among	O
the	O
accompanying	O
toolset	O
is	O
a	O
comprehensive	O
JavaScript	B-Language
parser	B-Language
that	O
is	O
an	O
integral	O
part	O
of	O
the	O
automatic	O
build	O
process	O
and	O
is	O
used	O
to	O
optimize	O
,	O
compress	B-General_Concept
,	O
link	O
and	O
deploy	B-Application
custom	O
applications	B-Application
,	O
and	O
generate	O
documentation	O
.	O
</s>
<s>
Internationalization	B-General_Concept
and	I-General_Concept
localization	I-General_Concept
of	O
applications	B-Application
are	O
supported	O
.	O
</s>
<s>
qooxdoo	B-Language
can	O
be	O
downloaded	O
as	O
a	O
comprehensive	O
SDK	B-Application
.	O
</s>
<s>
Despite	O
being	O
a	O
pure	O
JavaScript	B-Language
framework	I-Language
,	O
qooxdoo	B-Language
is	O
quite	O
on	O
par	O
with	O
GUI	B-Application
toolkits	B-Library
like	O
Qt	B-Language
,	O
Standard	B-Application
Widget	I-Application
Toolkit	I-Application
(	O
SWT	O
)	O
and	O
others	O
with	O
respect	O
to	O
implementing	O
user	B-Application
interfaces	I-Application
.	O
</s>
<s>
It	O
offers	O
a	O
set	O
of	O
widgets	O
that	O
resemble	O
elements	O
of	O
native	O
desktop	B-Application
applications	I-Application
.	O
</s>
<s>
Interface	O
description	O
is	O
done	O
programmatically	O
in	O
JavaScript	B-Language
for	O
enhanced	O
performance	O
.	O
</s>
<s>
Defining	O
the	O
user	B-Application
interface	I-Application
needs	O
no	O
HTML	B-Language
,	O
and	O
styling	O
the	O
interface	O
needs	O
no	O
Cascading	B-Language
Style	I-Language
Sheets	I-Language
(	O
CSS	B-Language
)	O
.	O
</s>
<s>
qooxdoo	B-Language
uses	O
a	O
closed	O
form	O
to	O
define	O
new	O
classes	O
.	O
</s>
<s>
Interfaces	B-Application
and	O
mixins	B-Language
are	O
defined	O
and	O
used	O
in	O
a	O
similar	O
fashion	O
.	O
</s>
<s>
While	O
being	O
a	O
client-side	O
and	O
server-agnostic	O
solution	O
,	O
the	O
qooxdoo	B-Language
project	O
does	O
include	O
optional	O
RPC	B-Operating_System
server	O
implementations	O
(	O
currently	O
in	O
Java	B-Language
,	O
PHP	B-Application
,	O
Perl	B-Language
and	O
Python	B-Language
)	O
to	O
demonstrate	O
client-server	O
communication	O
.	O
</s>
<s>
An	O
abstract	O
transport	O
layer	O
supports	O
queues	B-Application
,	O
timeouts	O
and	O
implementations	O
via	O
XMLHttpRequest	B-Protocol
,	O
Iframes	O
and	O
Scripts	O
.	O
</s>
<s>
Like	O
the	O
rest	O
of	O
qooxdoo	B-Language
,	O
this	O
layer	O
relies	O
on	O
event-based	O
programming	O
to	O
simplify	O
asynchronous	O
communication	O
.	O
</s>
