BBCode
BBCode ("Bulletin Board Code") is a lightweight markup language used to format messages in much Internet forum software, first introduced in 1998. The available "tags" of BBCode are usually indicated by square brackets ([ and ]) surrounding a keyword, and are parsed before being translated into HTML.[1]
Tags
    
| Example in HTML/CSS | BBCode | Output | ||||
|---|---|---|---|---|---|---|
| <b>bolded text</b>[2],<strong>bolded text</strong>[1] 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] | |||||
| <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.org English 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] |  | ||||
| <img src="Smileys/Face-smile.svg" alt=":-)"> | :)or[:-)]This would be another way to use the [img]url_img[/img]and must be pre-configured by the forum administrator.(This and other emoticons, depending on the variant. Most BBCodes do not enclose emoticons in square brackets, leading to frequent accidental usage.) |  (Specific image and size vary.) | ||||
| <blockquote><p>quoted text</p></blockquote>(Usually implemented in more advanced ways.) | [quote]quoted text[/quote][quote="author"]quoted text[/quote](including optional author) | Using a Wikipedia template: 
 
 | ||||
| <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> | [style size="30px"]Large Text[/style][style size="85"]Smaller Text[/style](The unit of measurement varies with each BBCode variant and could represent pixels, points, or relative HTML sizes.) | Large Text Smaller Text | ||||
| <span style="color:fuchsia;">Text in fuchsia</span>or<span style="color:#FF00FF;">Text in fuchsia</span> | [style color="fuchsia"]Text in fuchsia[/style]or[style color=#FF00FF]Text in fuchsia[/style]or[color=#FF00FF]Text in fuchsia[/color](Both HTML color names and hexadecimal color values are generally supported, although on some boards, you must omit the #from selecting a hexadecimal color.) | Text in fuchsia | ||||
| <ul>
  <li>Entry A</li>
  <li>Entry B</li>
</ul>
<ol>
  <li>Entry 1</li>
  <li>Entry 2</li>
</ol>
 | [list]
  [*]Entry A
  [*]Entry B
[/list]
[list=1]
  [*]Entry 1
  [*]Entry 2
[/list]
Some message boards do not need the square brackets around the markers.[3] (Many variants for  | 
 
 | ||||
| <table>
<tr>
  <td>table cell 1</td>
  <td>table cell 2</td>
</tr>
<tr>
  <td>table cell 3</td>
  <td>table cell 4</td>
</tr>
</table>
 | [table]
[tr]
  [td]table cell 1[/td]
  [td]table cell 2[/td]
[/tr]
[tr]
  [td]table cell 3[/td]
  [td]table cell 4[/td]
[/tr]
[/table]
(Some variants for  | 
 | 
Implementation
    
BBCode is typically implemented by applying a series of regular expression string-replace operations upon the input. Because regular expressions are limited in analyzing the structure of text input, this has the artifact that any non-hierarchical BBCode input will be transformed into invalid non-hierarchical HTML without error.
Applying traditional parsing techniques is made difficult by ambiguities in the markup, such as in [quote=[b]text[/b][/quote], where the input can either be interpreted as "text" quoted from someone called [b, or the bolded text "text" surrounded by [quote= and [/quote], i.e. [quote=text[/quote].
See also
    
    
References
    
- "Why modern forums are switching from HTML to BBCode". LovelyReality.com. Archived from the original on 2018-09-01. Retrieved 24 May 2015.
- "HTML Text Formatting". www.w3schools.com. Retrieved 2021-05-01.
- e.g. BOINC Project Forums et al.
- "BBCode tags reference". www.bbcode.org. Retrieved 12 January 2022.