<s>
JSFiddle	B-General_Concept
is	O
an	O
online	B-Application
IDE	I-Application
service	O
and	O
online	B-Architecture
community	I-Architecture
for	O
testing	O
and	O
showcasing	O
user-created	O
and	O
collaborational	O
HTML	B-Language
,	O
CSS	B-Language
and	O
JavaScript	B-Language
code	O
snippets	O
,	O
known	O
as	O
'	O
fiddles	O
 '	O
.	O
</s>
<s>
It	O
allows	O
for	O
simulated	O
AJAX	B-Device
calls	O
.	O
</s>
<s>
In	O
2019	O
,	O
JSFiddle	B-General_Concept
was	O
ranked	O
the	O
second	O
most	O
popular	O
online	B-Application
IDE	I-Application
by	O
the	O
PopularitY	O
of	O
Programming	O
Language	O
(	O
PYPL	O
)	O
index	O
based	O
on	O
the	O
number	O
of	O
times	O
it	O
was	O
searched	O
,	O
directly	O
behind	O
Cloud9	B-Application
IDE	I-Application
,	O
worldwide	O
and	O
in	O
the	O
USA	O
.	O
</s>
<s>
JSFiddle	B-General_Concept
is	O
an	O
online	B-Application
IDE	I-Application
which	O
is	O
designed	O
to	O
allow	O
users	O
to	O
edit	O
and	O
run	O
HTML	B-Language
,	O
JavaScript	B-Language
,	O
and	O
CSS	B-Language
code	O
on	O
a	O
single	O
page	O
.	O
</s>
<s>
Its	O
interface	O
is	O
minimalist	O
and	O
split	O
into	O
four	O
main	O
frames	O
,	O
which	O
correspond	O
to	O
editable	O
HTML	B-Language
,	O
JavaScript	B-Language
and	O
CSS	B-Language
fields	O
and	O
a	O
result	O
field	O
which	O
displays	O
the	O
user	O
's	O
project	O
after	O
it	O
is	O
run	O
.	O
</s>
<s>
Since	O
early	O
on	O
,	O
JSFiddle	B-General_Concept
adopted	O
smart	O
source-code	B-Application
editor	I-Application
with	O
programming	O
features	O
.	O
</s>
<s>
As	O
of	O
2020	O
,	O
JSFiddle	B-General_Concept
uses	O
CodeMirror	B-Language
to	O
support	O
its	O
editable	O
fields	O
,	O
providing	O
multicursors	B-Application
,	O
syntax	O
highlighting	O
,	O
syntax	B-Device
verification	I-Device
(	O
linter	B-Device
)	O
,	O
brace	B-Application
matching	I-Application
,	O
auto	O
indentation	O
,	O
autocompletion	O
,	O
code/text	B-Application
folding	I-Application
,	O
Search	O
and	O
Replace	O
to	O
assist	O
web	B-Operating_System
developers	I-Operating_System
in	O
their	O
actions	O
.	O
</s>
<s>
On	O
the	O
left	O
,	O
a	O
sidebar	O
allows	O
users	O
to	O
integrate	O
external	O
resources	O
such	O
as	O
external	O
CSS	B-Language
stylesheets	I-Language
and	O
external	O
JavaScript	B-Language
libraries	O
.	O
</s>
<s>
The	O
most	O
popular	O
JavaScript	B-Language
frameworks	O
and	O
CSS	B-Language
frameworks	O
are	O
suggested	O
to	O
users	O
and	O
available	O
via	O
a	O
click	O
.	O
</s>
<s>
JSFiddle	B-General_Concept
allows	O
users	O
to	O
publicly	O
save	O
their	O
code	O
an	O
uncapped	O
number	O
of	O
times	O
for	O
free	O
.	O
</s>
<s>
Code	O
saved	O
on	O
JSFiddle	B-General_Concept
may	O
also	O
be	O
edited	O
into	O
new	O
versions	O
,	O
shared	O
with	O
other	O
parties	O
,	O
and	O
forked	B-Application
into	O
a	O
new	O
line	O
.	O
</s>
<s>
JSFiddle	B-General_Concept
is	O
widely	O
used	O
among	O
web	B-Operating_System
developers	I-Operating_System
to	O
share	O
simple	O
tests	O
and	O
demonstrations	O
.	O
</s>
<s>
JSFiddle	B-General_Concept
is	O
also	O
widely	O
used	O
on	O
Stack	B-Error_Name
Overflow	I-Error_Name
,	O
the	O
dominant	O
question-answer	O
online	O
forum	O
for	O
the	O
web	O
industry	O
.	O
</s>
<s>
In	O
2009	O
,	O
JSFiddle	B-General_Concept
's	O
predecessor	O
,	O
MooShell	O
,	O
was	O
created	O
by	O
Piotr	O
Zalewa	O
as	O
a	O
website	O
application	O
which	O
was	O
exclusive	O
to	O
the	O
MooTools	O
community	O
.	O
</s>
<s>
In	O
2010	O
,	O
Oskar	O
Krawczyk	O
joined	O
the	O
project	O
as	O
a	O
developer	O
,	O
and	O
the	O
platform	O
was	O
made	O
freely	O
available	O
under	O
the	O
name	O
of	O
JSFiddle	B-General_Concept
.	O
</s>
<s>
In	O
2016	O
,	O
JSFiddle	B-General_Concept
underwent	O
a	O
full	O
platform	O
overhaul	O
and	O
became	O
ad-sponsored	O
.	O
</s>
