This document is a guide to the mark-up styles used throughout the site. Parts of this markup guide are attributable to Dave Shea, and licensed under a Creative Commons License.

Sections

The main page header of this guide is an h1 element. Any header elements may include links, as depicted in the example.

The secondary header above is an h2 element, which may be used for any form of important page-level header. More than one may be used per page. Consider using an h2 unless you need a header level of less importance, or as a sub-header to an existing h2 element.

Third-Level Header

The header above is an h3 element, which may be used for any form of page-level header which falls below the h2 header in a document hierarchy.

Fourth-Level Header

The header above is an h4 element, which may be used for any form of page-level header which falls below the h3 header in a document hierarchy.

Fifth-Level Header

The header above is an h5 element, which may be used for any form of page-level header which falls below the h4 header in a document hierarchy.

Sixth-Level Header

The header above is an h6 element, which may be used for any form of page-level header which falls below the h5 header in a document hierarchy.

Grouping content

Paragraphs

All paragraphs are wrapped in p tags. Additionally, p elements can be wrapped with a blockquote element if the p element is indeed a quote. Historically, blockquote has been used purely to force indents, but this is now achieved using CSS. Reserve blockquote for quotes.

Horizontal rule

The hr element represents a paragraph-level thematic break, e.g. a scene change in a story, or a transition to another topic within a section of a reference book. The following extract from Pandora’s Star by Peter F. Hamilton shows two paragraphs that precede a scene change and the paragraph that follows it:

Pre-formatted text

The pre element represents a block of pre-formatted text, in which structure is represented by typographic conventions rather than by elements. Such examples are an e-mail (with paragraphs indicated by blank lines, lists indicated by lines prefixed with a bullet), fragments of computer code (with structure indicated according to the conventions of that language) or displaying ASCII art. Here’s an example showing the printable characters of ASCII:

  ! " # $ % & ' ( ) * + , - . /
                    0 1 2 3 4 5 6 7 8 9 : ; < = > ?
                    @ A B C D E F G H I J K L M N O
                    P Q R S T U V W X Y Z [ \ ] ^ _
                    ` a b c d e f g h i j k l m n o
                    p q r s t u v w x y z { | } ~ 

Blockquotes

The blockquote element represents a section that is being quoted from another source.

Additionally, you might wish to cite the source, as in the above example. The correct method involves including the cite attribute on the blockquote element, but since no browser makes any use of that information, it’s useful to link to the source also.

Ordered list

The ol element denotes an ordered list, and various numbering schemes are available through the CSS (including 1,2,3… a,b,c… i,ii,iii… and so on). Each item requires a surrounding <li> and </li> tag, to denote individual items within the list (as you may have guessed, li stands for list item).

Unordered list

The ul element denotes an unordered list (ie. a list of loose items that don’t require numbering, or a bulleted list). Again, each item requires a surrounding <li> and </li> tag, to denote individual items. Here is an example list showing the constituent parts of the British Isles:

Sometimes we may want each list item to contain block elements, typically a paragraph or two.

Definition list

The dl element is for another type of list called a definition list. Instead of list items, the content of a dl consists of dt (Definition Term) and dd (Definition description) pairs. Though it may be called a “definition list”, dl can apply to other scenarios where a parent/child relationship is applicable. For example, it may be used for marking up dialogues, with each dt naming a speaker, and each dd containing his or her words.

Figures

Figures are usually used to refer to images:

Here, a part of a poem is marked up using figure:

Text-level Semantics

There are a number of inline HTML elements you may use anywhere within other elements.

Links and anchors

The a element is used to hyperlink text, be that to another page, a named fragment on the current page or any other location on the web. Example:

Stressed emphasis

The em element is used to denote text with stressed emphasis, i.e., something you’d pronounce differently. Where italicizing is required for stylistic differentiation, the i element may be preferable. Example:

Strong importance

The strong element is used to denote text with strong importance. Where bolding is used for stylistic differentiation, the b element may be preferable. Example:

Small print

The small element is used to represent disclaimers, caveats, legal restrictions, or copyrights (commonly referred to as ‘small print’). It can also be used for attributions or satisfying licensing requirements. Example:

Strikethrough

The s element is used to represent content that is no longer accurate or relevant. When indicating document edits i.e., marking a span of text as having been removed from a document, use the del element instead. Example:

Citations

The cite element is used to represent the title of a work (e.g. a book, essay, poem, song, film, TV show, sculpture, painting, musical, exhibition, etc). This can be a work that is being quoted or referenced in detail (i.e. a citation), or it can just be a work that is mentioned in passing. Example:

Inline quotes

The q element is used for quoting text inline. Example showing nested quotations:

Definition

The dfn element is used to highlight the first use of a term. The title attribute can be used to describe the term. Example:

Abbreviation

The abbr element is used for any abbreviated text, whether it be acronym, initialism, or otherwise. Generally, it’s less work and useful (enough) to mark up only the first occurrence of any particular abbreviation on a page, and ignore the rest. Any text in the title attribute will appear when the user’s mouse hovers the abbreviation (although notably, this does not work in Internet Explorer for Windows). Example abbreviations:

Time

The time element is used to represent either a time on a 24 hour clock, or a precise date in the proleptic Gregorian calendar, optionally with a time and a time-zone offset. Example:

Code

The code element is used to represent fragments of computer code. Useful for technology-oriented sites, not so useful otherwise. Example:

Used in conjunction with the pre element:

function getJelly() {
                        echo $aDeliciousSnack;
                    }

Shown with line numbers:

Variable

The var element is used to denote a variable in a mathematical expression or programming context, but can also be used to indicate a placeholder where the contents should be replaced with your own value. Example:

Sample output

The samp element is used to represent (sample) output from a program or computing system. Useful for technology-oriented sites, not so useful otherwise. Example:

Keyboard entry

The kbd element is used to denote user input (typically via a keyboard, although it may also be used to represent other input methods, such as voice commands). Example:

f478b9aa89442d2922b915a23dd1ac4c

Superscript and subscript text

The sup element represents a superscript and the sub element represents a sub. These elements must be used only to mark up typographical conventions with specific meanings, not for typographical presentation. As a guide, only use these elements if their absence would change the meaning of the content. Example:

Italicised

The i element is used for text in an alternate voice or mood, or otherwise offset from the normal prose. Examples include taxonomic designations, technical terms, idiomatic phrases from another language, the name of a ship or other spans of text whose typographic presentation is typically italicised. Example:

Emboldened

The b element is used for text stylistically offset from normal prose without conveying extra importance, such as key words in a document abstract, product names in a review, or other spans of text whose typographic presentation is typically emboldened. Example:

Marked or highlighted text

The mark element is used to represent a run of text marked or highlighted for reference purposes. When used in a quotation it indicates a highlight not originally present but added to bring the reader’s attention to that part of the text. When used in the main prose of a document, it indicates a part of the document that has been highlighted due to its relevance to the user’s current activity. Example:

Edits

The del element is used to represent deleted or retracted text which still must remain on the page for some reason. Meanwhile its counterpart, the ins element, is used to represent inserted text. Both del and ins have a datetime attribute which allows you to include a timestamp directly in the element. Example inserted text and usage:

Tabular data

Tables should be used when displaying tabular data. The thead, tfoot and tbody elements enable you to group rows within each a table.

If you use these elements, you must use every element. They should appear in this order: thead, tfoot and tbody, so that browsers can render the foot before receiving all the data. You must use these tags within the table element.

Forms

Forms can be used when you wish to collect data from users. The fieldset element enables you to group related fields within a form, and each one should contain a corresponding legend. The label element ensures field descriptions are associated with their corresponding form widgets.

Patterns

Design and mark-up patterns unique to this site.

Pagination

Used to navigate between pages of search results.

Notification Message

Used to highlight a particular message or action.