<s>
BBCode	B-Language
(	O
"	O
Bulletin	B-Language
Board	I-Language
Code	I-Language
"	O
)	O
is	O
a	O
lightweight	B-Protocol
markup	I-Protocol
language	I-Protocol
used	O
to	O
format	O
messages	O
in	O
many	O
Internet	B-Application
forum	I-Application
software	I-Application
.	O
</s>
<s>
The	O
available	O
"	O
tags	O
"	O
of	O
BBCode	B-Language
are	O
usually	O
indicated	O
by	O
square	O
brackets	O
( [	O
and	O
]	O
)	O
surrounding	O
a	O
keyword	O
,	O
and	O
are	O
parsed	B-Language
before	O
being	O
translated	O
into	O
HTML	B-Language
.	O
</s>
<s>
Example	O
in	O
HTML/CSS	O
BBCode	B-Language
Output	O
<b>bolded text</b>,<strong>bolded text</strong> or<span style="font-weight: bold;">bolded text</span> [b]bolded text[/b] bolded text <i>italicized text</i>,<em>italicized text</em> or<span style="font-style: italic;">italicized text</span> [i]italicized text[/i] italicized text <ins>underlined text</ins> or<span style="text-decoration: underline;">underlined text</span> [u]underlined text[/u] underlined text <del>strikethrough text</del> or<span style="text-decoration: line-through;">strikethrough text</span> [s]strikethrough text[/s] strikethrough text <a href="https://en.wikipedia.org">https://en.wikipedia.org</a><a href="https://en.wikipedia.org">English Wikipedia</a> [url]https://en.wikipedia.org[/url][url=https://en.wikipedia.org]English Wikipedia[/url] https://en.wikipedia.orgEnglish Wikipedia <img src="https://upload.wikimedia.org/wikipedia/commons/7/70/Example.png" alt="Example.png" /> [img]https://upload.wikimedia.org/wikipedia/commons/7/70/Example.png[/img] 172px|link= <img src="Smileys/Face-smile.svg" alt=":- ) ">	O
:	O
)	O
or	O
[	O
:	O
-	O
)	O
]	O
This	O
would	O
be	O
another	O
way	O
to	O
use	O
the	O
 [ img ] url_img [ /img ] 	O
and	O
must	O
be	O
pre-configured	O
by	O
the	O
forum	O
administrator	O
.	O
</s>
<s>
(	O
This	O
and	O
other	O
emoticons	B-Protocol
,	O
depending	O
on	O
the	O
variant	O
.	O
</s>
<s>
Most	O
BBCodes	B-Language
do	O
not	O
enclose	O
emoticons	B-Protocol
in	O
square	O
brackets	O
,	O
leading	O
to	O
frequent	O
accidental	O
usage	O
.	O
)	O
</s>
<s>
[quote]quoted	O
text[/quote][quote="author"]quoted	O
text[ 	O
/quote	O
]( including	O
optional	O
author	O
)	O
Using	O
a	O
Wikipedia	O
template	O
:	O
<pre>monospaced text</pre> [code]monospaced text[/code] monospaced text <span style="font-size:30px">Large Text</span> or<span style="font-size:85%">Smaller Text</span>	O
[	O
style	O
size	O
=	O
"	O
30px	O
"	O
 ]Large	O
Text[ 	O
/style	O
][style	O
size	O
=	O
"	O
85	O
"	O
 ]Smaller	O
Text[ 	O
/style	O
]( The	O
unit	O
of	O
measurement	O
varies	O
with	O
each	O
BBCode	B-Language
variant	O
and	O
could	O
represent	O
pixels	O
,	O
points	O
,	O
or	O
relative	O
HTML	B-Language
sizes	O
.	O
)	O
</s>
<s>
Large	O
TextSmaller	O
Text	O
<span style="color:fuchsia;">Text in fuchsia</span> or<span style="color:#FF00FF;">Text in fuchsia</span>	O
[	O
style	O
color	O
=	O
"	O
fuchsia	O
"	O
 ]Text	O
in	O
fuchsia[/style]	O
or[ style	O
color	O
=	O
#FF00FF	O
 ]Text	O
in	O
fuchsia[/style]	O
or[color=#FF00FF]Text	O
in	O
fuchsia[ 	O
/color	O
]( Both	O
HTML	B-Language
color	O
names	O
and	O
hexadecimal	O
color	O
values	O
are	O
generally	O
supported	O
,	O
although	O
on	O
some	O
boards	O
,	O
you	O
must	O
omit	O
the	O
#	O
from	O
selecting	O
a	O
hexadecimal	O
color	O
.	O
)	O
</s>
<s>
Some	O
message	B-Application
boards	I-Application
do	O
not	O
need	O
the	O
square	O
brackets	O
around	O
the	O
markers.e.g.	O
</s>
<s>
BBCode	B-Language
is	O
typically	O
implemented	O
by	O
applying	O
a	O
series	O
of	O
regular	B-Language
expression	I-Language
string-replace	O
operations	O
upon	O
the	O
input	O
.	O
</s>
<s>
Because	O
regular	B-Language
expressions	I-Language
are	O
limited	O
in	O
analyzing	O
the	O
structure	O
of	O
text	O
input	O
,	O
this	O
has	O
the	O
artifact	O
that	O
any	O
non-hierarchical	O
BBCode	B-Language
input	O
will	O
be	O
transformed	O
into	O
invalid	O
non-hierarchical	O
HTML	B-Language
without	O
error	O
.	O
</s>
<s>
Applying	O
traditional	O
parsing	B-Language
techniques	O
is	O
made	O
difficult	O
by	O
ambiguities	O
in	O
the	O
markup	O
,	O
such	O
as	O
in	O
,	O
where	O
the	O
input	O
can	O
either	O
be	O
interpreted	O
as	O
"	O
text	O
"	O
quoted	O
from	O
someone	O
called	O
,	O
or	O
the	O
bolded	O
text	O
"	O
text	O
"	O
surrounded	O
by	O
and	O
,	O
i.e.	O
</s>
