<s>
The	O
Yahoo	B-Application
!	I-Application
</s>
<s>
User	O
Interface	O
Library	O
(	O
YUI	O
)	O
is	O
a	O
discontinued	O
open-source	O
JavaScript	B-Language
library	I-Language
for	O
building	O
richly	O
interactive	O
web	B-Application
applications	I-Application
using	O
techniques	O
such	O
as	O
Ajax	B-General_Concept
,	O
DHTML	B-General_Concept
,	O
and	O
DOM	B-Language
scripting	I-Language
.	O
</s>
<s>
YUI	O
includes	O
several	O
core	O
CSS	B-Language
resources	O
.	O
</s>
<s>
It	O
is	O
available	O
under	O
a	O
BSD	B-Operating_System
License	I-Operating_System
.	O
</s>
<s>
Development	O
on	O
YUI	O
began	O
in	O
2005	O
and	O
Yahoo	B-Application
!	I-Application
</s>
<s>
properties	O
such	O
as	O
My	O
Yahoo	B-Application
!	I-Application
</s>
<s>
and	O
the	O
Yahoo	B-Application
!	I-Application
</s>
<s>
It	O
was	O
actively	O
developed	O
by	O
a	O
core	O
team	O
of	O
Yahoo	B-Application
!	I-Application
</s>
<s>
In	O
September	O
2009	O
,	O
Yahoo	B-Application
!	I-Application
</s>
<s>
released	O
YUI	B-Language
3	I-Language
,	O
a	O
new	O
version	O
of	O
YUI	O
rebuilt	O
from	O
the	O
ground	O
up	O
to	O
modernize	O
the	O
library	O
and	O
incorporate	O
lessons	O
learned	O
from	O
YUI	B-Language
2	I-Language
.	O
</s>
<s>
Among	O
the	O
enhancements	O
are	O
a	O
CSS	B-Language
selector	O
driven	O
engine	O
,	O
like	O
jQuery	B-Language
,	O
for	O
retrieving	O
DOM	B-General_Concept
elements	O
,	O
a	O
greater	O
emphasis	O
on	O
granularity	O
of	O
modules	O
,	O
a	O
smaller	O
seed	O
file	O
that	O
loads	O
other	O
modules	O
when	O
necessary	O
,	O
and	O
a	O
variety	O
of	O
syntactic	O
changes	O
intended	O
to	O
make	O
writing	O
code	O
faster	O
and	O
easier	O
.	O
</s>
<s>
The	O
YUI	B-Language
Library	I-Language
project	O
at	O
Yahoo	B-Application
!	I-Application
</s>
<s>
was	O
founded	O
by	O
Thomas	O
Sha	O
and	O
sponsored	O
internally	O
by	O
Yahoo	B-Application
!	I-Application
</s>
<s>
On	O
August	O
29	O
,	O
2014	O
,	O
it	O
was	O
announced	O
that	O
active	O
development	O
of	O
YUI	O
by	O
Yahoo	B-Application
!	I-Application
</s>
<s>
would	O
end	O
,	O
citing	O
the	O
evolution	O
of	O
the	O
JavaScript	B-Language
standards	O
,	O
steadily	O
decreasing	O
interest	O
in	O
large	O
JavaScript	B-Language
libraries	I-Language
by	O
developers	O
,	O
and	O
the	O
proliferation	O
of	O
server-side	O
solutions	O
.	O
</s>
<s>
Future	O
development	O
will	O
be	O
limited	O
to	O
maintenance	O
releases	O
addressing	O
issues	O
that	O
are	O
"	O
absolutely	O
critical	O
to	O
Yahoo	B-Application
properties.	O
"	O
</s>
<s>
The	O
YUI	B-Language
Library	I-Language
is	O
fully	O
documented	O
on	O
its	O
website	O
;	O
detailed	O
API	O
documentation	O
accompanies	O
the	O
library	O
download	O
.	O
</s>
<s>
It	O
has	O
six	O
types	O
of	O
components	O
:	O
YUI	O
core	O
,	O
utilities	O
,	O
UI	O
controls	O
,	O
CSS	B-Language
components	O
,	O
developer	O
tools	O
,	O
and	O
build	O
tools	O
.	O
</s>
<s>
The	O
YUI	O
Core	O
is	O
a	O
light	O
(	O
31KB	O
minified	O
)	O
set	O
of	O
tools	O
for	O
event	O
management	O
and	O
DOM	B-General_Concept
manipulation	O
.	O
</s>
<s>
Helps	O
with	O
common	O
DOM	B-Language
scripting	I-Language
tasks	O
,	O
including	O
element	O
positioning	O
and	O
CSS	B-Language
style	I-Language
management	O
.	O
</s>
<s>
Provides	O
developers	O
with	O
easy	O
and	O
safe	O
access	O
to	O
browser	O
events	B-Application
(	O
such	O
as	O
mouse	O
clicks	O
and	O
key	O
presses	O
)	O
.	O
</s>
<s>
It	O
also	O
provides	O
the	O
Custom	O
Event	O
object	O
for	O
publishing	O
and	O
subscribing	O
to	O
custom	O
events	B-Application
.	O
</s>
<s>
Helps	O
web	B-Application
applications	I-Application
use	O
the	O
browser	O
's	O
back	O
button	O
and	O
bookmarking	O
functionality	O
.	O
</s>
<s>
Helps	O
manage	O
XMLHttpRequest	B-Protocol
transactions	O
in	O
a	O
cross-browser	B-Architecture
fashion	O
.	O
</s>
<s>
It	O
has	O
integrated	O
support	O
for	O
form	B-General_Concept
posts	O
,	O
error	B-General_Concept
handling	I-General_Concept
,	O
callbacks	O
and	O
file	O
uploading	O
.	O
</s>
<s>
Allows	O
you	O
to	O
manage	O
browser	B-Application
cookies	I-Application
and	O
subcookies	O
through	O
a	O
simple	O
API	O
.	O
</s>
<s>
Provides	O
a	O
common	O
configurable	O
interface	O
for	O
other	O
components	O
to	O
interact	O
with	O
different	O
types	O
of	O
data	O
,	O
from	O
simple	O
JavaScript	B-Language
arrays	O
to	O
online	O
servers	O
over	O
XHR	B-Protocol
.	O
</s>
<s>
The	O
YUI	O
Drag	O
and	O
Drop	O
Utility	O
makes	O
it	O
easy	O
to	O
make	O
elements	O
"	O
draggable	O
"	O
and	O
to	O
create	O
drop	O
targets	O
that	O
respond	O
to	O
drag	O
events	B-Application
.	O
</s>
<s>
Provides	O
a	O
wrapper	O
for	O
HTML	B-General_Concept
elements	I-General_Concept
in	O
the	B-General_Concept
DOM	I-General_Concept
and	O
makes	O
simpler	O
common	O
tasks	O
such	O
as	O
adding	O
listeners	O
,	O
manipulating	O
the	B-General_Concept
DOM	I-General_Concept
,	O
and	O
setting	O
and	O
getting	O
attributes	O
.	O
</s>
<s>
The	O
Get	O
Utility	O
supports	O
the	O
asynchronous	O
loading	O
of	O
data	O
and	O
scripts	O
through	O
script	O
nodes	O
and	O
the	O
dynamic	O
loading	O
of	O
external	O
CSS	B-Language
files	O
.	O
</s>
<s>
The	O
JSON	B-General_Concept
Utility	O
provides	O
methods	O
for	O
validation	O
of	O
incoming	O
JSON	B-General_Concept
data	O
to	O
verify	O
that	O
it	O
is	O
safe	O
and	O
methods	O
to	O
convert	O
JavaScript	B-Language
data	O
to	O
a	O
JSON-formatted	O
string	O
.	O
</s>
<s>
These	O
methods	O
are	O
based	O
on	O
Douglas	O
Crockford	O
's	O
work	O
at	O
JSON.org	O
.	O
</s>
<s>
Allows	O
you	O
to	O
make	O
any	O
block-level	O
HTML	B-General_Concept
element	I-General_Concept
resizable	O
.	O
</s>
<s>
The	O
YUI	O
Selector	O
Utility	O
allows	O
you	O
to	O
grab	O
references	O
to	O
HTML	B-General_Concept
elements	I-General_Concept
via	O
CSS3	O
selector	O
syntax	O
.	O
</s>
<s>
It	O
also	O
supports	O
server-side	O
data-sources	O
via	O
XMLHttpRequest	B-Protocol
.	O
</s>
<s>
Enables	O
the	O
creation	O
of	O
rich	O
,	O
graphical	O
buttons	O
that	O
function	O
like	O
traditional	O
HTML	B-General_Concept
form	I-General_Concept
buttons	O
.	O
</s>
<s>
Supports	O
a	O
variety	O
of	O
DHTML	B-General_Concept
windowing	O
patterns	O
including	O
Tooltip	O
,	O
Panel	O
,	O
Dialog	O
,	O
SimpleDialog	O
,	O
Module	O
and	O
Overlay	O
.	O
</s>
<s>
Allows	O
you	O
to	O
create	O
cross-browser	B-Architecture
,	O
pixel	O
perfect	O
layouts	O
with	O
little	O
effort	O
by	O
providing	O
a	O
fixed	O
layout	O
containing	O
,	O
top	O
,	O
bottom	O
,	O
left	O
,	O
right	O
and	O
center	O
layout	O
units	O
.	O
</s>
<s>
The	O
YUI	B-Application
Rich	I-Application
Text	I-Application
Editor	I-Application
is	O
a	O
sophisticated	O
client-side	O
text-processor	O
that	O
is	O
modular	O
and	O
highly	O
configurable	O
,	O
suitable	O
for	O
any	O
open-ended	O
text-entry	O
situation	O
.	O
</s>
<s>
Provides	O
navigable	O
tabbed	O
views	O
of	O
content	O
;	O
supports	O
dynamic	O
loading	O
of	O
tab	O
content	O
via	O
XMLHttpRequest	B-Protocol
.	O
</s>
<s>
Use	O
Base	O
after	O
Reset	O
to	O
provide	O
a	O
consistent	O
,	O
cross-browser	B-Architecture
replacement	O
for	O
the	O
standard	O
browser	O
CSS	B-Language
rules	O
to	O
which	O
web	O
developers	O
are	O
accustomed	O
.	O
</s>
<s>
Standardized	O
cross-browser	B-Architecture
font	O
families	O
and	O
size	O
rendering	O
.	O
</s>
<s>
CSS	B-Language
declarations	O
remove	O
margins	O
and	O
standardize	O
cross-browser	B-Architecture
rendering	O
on	O
common	O
elements	O
.	O
</s>
<s>
Provides	O
a	O
quick	O
and	O
easy	O
way	O
to	O
write	O
log	O
messages	O
to	O
an	O
on-screen	O
console	O
,	O
the	O
Firebug	B-Operating_System
extension	O
for	O
Mozilla	B-Application
Firefox	I-Application
,	O
or	O
the	O
Safari	B-Application
JavaScript	B-Language
console	O
.	O
</s>
<s>
A	O
cross-browser	B-Architecture
,	O
non-visual	O
code	O
profiler	O
for	O
JavaScript	B-Language
.	O
</s>
<s>
YUI	O
Test	O
is	O
a	O
testing	O
framework	O
for	O
browser-based	B-Application
JavaScript	B-Language
solutions	O
.	O
</s>
<s>
Using	O
YUI	O
Test	O
,	O
you	O
can	O
easily	O
add	O
unit	O
testing	O
to	O
your	O
JavaScript	B-Language
solutions	O
.	O
</s>
<s>
YUI	O
Compressor	O
is	O
a	O
tool	O
that	O
minifies	O
JavaScript	B-Language
and	O
CSS	B-Language
safely	O
.	O
</s>
<s>
YUIDoc	O
is	O
a	O
tool	O
written	O
in	O
JavaScript	B-Language
that	O
generates	O
searchable	O
API	O
documentation	O
of	O
JavaScript	B-Language
code	O
.	O
</s>
