<s>
An	O
online	B-Application
rich-text	I-Application
editor	I-Application
is	O
the	O
interface	O
for	O
editing	O
rich	O
text	O
within	O
web	B-Application
browsers	I-Application
,	O
which	O
presents	O
the	O
user	O
with	O
a	O
"	B-Application
what-you-see-is-what-you-get	I-Application
"	I-Application
(	O
WYSIWYG	B-Application
)	O
editing	O
area	O
.	O
</s>
<s>
The	O
aim	O
is	O
to	O
reduce	O
the	O
effort	O
for	O
users	O
trying	O
to	O
express	O
their	O
formatting	O
directly	O
as	O
valid	O
HTML	B-General_Concept
markup	I-General_Concept
.	O
</s>
<s>
Though	O
very	O
early	O
browsers	B-Application
could	O
display	O
rich	O
text	O
,	O
user	O
data	O
entry	O
was	O
limited	O
to	O
text	O
boxes	O
with	O
a	O
single	O
font	O
and	O
style	O
(	O
implemented	O
with	O
the	O
<textarea>	O
HTML	B-General_Concept
element	I-General_Concept
)	O
.	O
</s>
<s>
Internet	O
Explorer	O
was	O
the	O
first	O
to	O
add	O
a	O
special	O
"	O
designMode	O
"	O
which	O
allowed	O
formatted	O
parts	O
of	O
a	O
document	O
to	O
be	O
edited	O
by	O
the	O
user	O
using	O
a	O
cursor	B-Application
.	O
</s>
<s>
Mozilla	O
followed	O
suit	O
in	O
version	O
1.3	O
,	O
and	O
most	O
major	O
browsers	B-Application
now	O
implement	O
this	O
informal	O
standard	O
in	O
some	O
capacity	O
.	O
</s>
<s>
The	O
technical	O
capabilities	O
needed	O
to	O
implement	O
an	O
online	O
rich	O
text	B-Application
editor	I-Application
were	O
not	O
covered	O
by	O
the	O
W3C	O
specifications	O
for	O
HTML4	O
.	O
</s>
<s>
Nevertheless	O
,	O
popular	O
services	O
like	O
Gmail	B-Application
and	O
WordPress	B-Application
have	O
relied	O
on	O
rich	O
text	B-Application
editing	I-Application
as	O
their	O
main	O
user	O
interface	O
.	O
</s>
<s>
With	O
HTML5	B-Application
,	O
some	O
standardization	O
was	O
made	O
on	O
a	O
DOM	O
property	O
called	O
"	O
contentEditable	O
"	O
which	O
resembles	O
Internet	O
Explorer	O
's	O
original	O
extension	O
.	O
</s>
<s>
Many	O
of	O
the	O
online	B-Application
office	I-Application
suites	I-Application
tend	O
to	O
provide	O
online	O
text	B-Application
editing	I-Application
and	O
formatting	O
functionality	O
.	O
</s>
<s>
The	O
majority	O
of	O
online	B-Application
rich	I-Application
text	I-Application
editors	I-Application
use	O
an	O
iframe	O
element	O
for	O
the	O
content	O
area	O
.	O
</s>
<s>
Some	O
editors	O
use	O
div	B-General_Concept
elements	I-General_Concept
for	O
their	O
content	O
area	O
.	O
</s>
<s>
These	O
editors	O
include	O
Aloha	O
Editor	O
,	O
CKEditor	B-Application
,	O
SnapEditor	B-General_Concept
and	O
TinyMCE	B-Application
.	O
</s>
<s>
Editors	O
that	O
use	O
an	O
iframe	O
,	O
to	O
avoid	O
styling	O
conflicts	O
,	O
include	O
CKEditor	B-Application
,	O
Dijit	O
Editor	O
and	O
TinyMCE	B-Application
.	O
</s>
