# BBCode

BBCode ("Bulletin Board Code") is a lightweight markup language used to format messages in many Internet forum software. It was 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.

## Tags

| Example in HTML/CSS | BBCode | Output |
| <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.org English Wikipedia |
| <img src="https://upload.wikimedia.org/wikipedia/commons/7/70/Example.png" alt="This is just an example" /> | [img alt="This is just an example" ]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: quoted textquoted text— author |
| <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. (Many variants for li and /li, list types – unordered and ordered, with different bullets or counter formats – etc.) | Entry A Entry B Entry 1 Entry 2 |
| <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 thead, rules, etc.) | table cell 1 table cell 2 table cell 3 table cell 4 |
| Source: |||

## 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].