Wikipedia:Manual of Style/Lists

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This page is about lists in Wikipedia articles. For Wikipedia's mailing lists, see Wikipedia:Mailing lists. For the WikiProject, see Wikipedia:WikiProject Lists. For other information about lists, see Wikipedia:Lists.

Lists are commonly used in Wikipedia to organize information. Lists may be found within the body of a prose article, or as a stand-alone article. This guideline explains when and how to use lists appropriately.

Types of lists[edit]

A list can stand alone as a self-contained page, or it can be embedded in an article.

List articles[edit]

List articles are encyclopedia pages consisting of a lead section followed by a list (which may or may not be divided by headings). The items on these lists include links to articles in a particular subject area, and may include additional information about the listed items. The titles of list articles typically begin with the type of list it is (List of, Index of, etc.), followed by the article's subject; like: List of vegetable oils. They can be organised alphabetically, by subject classification or by topics in a flat or hierarchical structure.

The title and bullet style or vertical style is common for list articles. These Wikipedia articles follow the Wikipedia:Stand-alone lists style guideline.[clarification needed]

Types of list articles include:

  • A Glossary page presents encyclopedically explanatory definitions for specialized terms in a subject area. Glossaries contain a small working vocabulary and definitions for important, unique or frequently encountered concepts, usually including idioms or metaphors particular to a subject area. For more information, see Wikipedia:Manual of Style (glossaries) (a draft guideline).
  • An Index of articles page presents an alphabetical list of articles related to the subject of the index.
  • A Bibliography page presents a list of relevant books, journal or other references for a subject area. Bibliographies are useful for expanding Further Reading topics for Summary style articles.
  • A Discography page presents a listing of all recordings which a musician or singer features. Additionally, discographies may be compiled based on a particular musical genre or record label, etc.
  • A Timeline is a graphical representation of a chronological sequence of events.
  • An Etymology is a list of the origin and histories of words with a common theme.
  • Set index articles document a set of items that share the same (or a similar) name. They are different from disambiguation pages in that they are fully-fledged articles meant to document multiple subjects, while disambiguation pages are for navigation purposes only.
  • Dynamic lists change as the subjects they cover change, and may never be completed.

Embedded lists[edit]

Embedded lists are lists used within articles to present information that supplements the article's prose content. Wikipedia also uses several types of standard appendices, usually in list format, including "See also", "References", and "External links" sections, as well as navigational templates.

Purposes of lists[edit]

Shortcuts:

Lists have three main purposes:

Information[edit]

The list may be a valuable information source. This is particularly the case for a structured list. Examples would include lists organized chronologically, grouped by theme, or annotated lists.

Navigation[edit]

Lists which contain internally linked terms (i.e., wikilinks) serve, in aggregate, as natural tables of contents and indexes of Wikipedia. If users have some general idea of what they are looking for but do not know the specific terminology, they could browse the lists of basic topics and more comprehensive lists of topics, which in turn lead to most if not all of Wikipedia's lists, which in turn lead to related articles. Users without a specific research goal in mind might also find the articles listed in articles' see also sections useful. Lists are also provided in portals to assist in navigating their subjects, and lists are often placed in articles via the use of series boxes and other navigational templates.

Users with a specific research goal, described in one or two words, are likely to find Wikipedia's search box useful.

Development[edit]

Some lists are useful for Wikipedia development purposes. The lists of related topics give an indication of the state of Wikipedia, the articles that have been written, and the articles that have yet to be written. However, as Wikipedia is optimized for readers over editors, any lists which exist primarily for development or maintenance purposes (such as a list that consists entirely of red links and does not serve an informational purpose; especially a list of missing topics) should be in either the project or user space, not the main space.

Lists and categories[edit]

Redundancy of lists and categories is beneficial because the two formats work together; the principle is covered in the guideline Wikipedia:Categories, lists, and navigation templates. Like categories, lists can be used for keeping track of changes in the listed pages, using the Related Changes feature. Unlike a category, a list also allows detection of deletion of its entries, and, more generally, a history of its contents is available; lists also permit a large number of entries to appear on a single page.

List naming[edit]

For a stand-alone list the list's title is the page name. For an embedded list, the list's title is usually a section title (for instance Latin Empire#Latin Emperors of Constantinople, 1204–1261), but it can be shorter. The list title should not be misleading (and should normally not include abbreviations), but overly precise list titles can be less useful (and make the list difficult to find); the precise inclusion criterion of the list should be spelled out in the lead section (see below), not the title. For instance, words like complete, and notable are normally excluded from list titles. Instead, the lead makes clear whether the list is complete, or is limited to widely known or notable members (i.e., those that merit articles). Note that the word "famous" is considered an unnecessary "peacock" embellishment and should not be used.

List layout[edit]

Lead section or paragraph[edit]

Shortcut:

The contents of an article that is a stand-alone list should be clear. If the title does not already clarify what the list includes, then the list's lead section should do so. Don't leave readers confused over the list's inclusion criteria or have editors guessing what may be added to the list.

However short or schematic a list description, Wikipedia:Neutral point of view applies, including:

It should not be asserted that the most popular view or some sort of intermediate view among the different views is the correct one.

Lead sections and paragraphs should also not go counter to the recommendations of the Self-references to avoid guideline.

Lead sections in stand-alone lists[edit]

Stand-alone lists should always include a lead section just as other articles do.

Wikipedia:Featured list criteria recommends that "[a list] has an engaging lead section that introduces the subject, and defines the scope and inclusion criteria of the list".

Further, non-obvious characteristics of a list, for instance regarding the list's structure, should be explained in its lead section (example: List of compositions by Johann Sebastian Bach), or in a separate introductory section (example: List of compositions by Franz Schubert#How Schubert's compositions are listed).

Lists should not be used to create content forks between a topic that has a separate Wikipedia article (e.g. "republic") and a list complementary to that topic (e.g. "List of republics").

Lead paragraphs in embedded lists[edit]

Shortcut:

Embedded lists should have a lead paragraph in cases where the title is ambiguous or when the list has non-obvious characteristics.

Organization[edit]

Although lists may be organized in different ways, they must always be organized. The most basic form of organization is alphabetical or numerical (such as List of Star Wars starfighters), though if items have specific dates a chronological format is sometimes preferable (List of Belarusian Prime Ministers). When using a more complex form of organization, (by origin, by use, by type, etc.), the criteria for categorization must be clear and consistent. Just as a reader or editor could easily assume that the headings A, B, C would be followed by D (rather than 1903), more complex systems should be just as explicit. If a list of Australians in international prisons contains the headings Argentina and Cambodia (organization by country), it would be inappropriate for an editor to add the heading Drug trafficking (organization by offense). If a list entry logically belongs in two or more categories (e.g., an Australian in an Argentine prison for drug trafficking), this suggests that the list categorization might be flawed, and should be re-examined.

Lists should never contain Unsorted or Miscellaneous headings, as all items worthy of inclusion in the list can be sorted by some criteria, although it is entirely possible that the formatting of the list would need to be revamped to include all appropriate items. Not-yet-sorted items may be included on the list's talk page while their categorization is determined.

Adding individual items to a list[edit]

Shortcut:

Lists, whether they are stand-alone lists (also called list articles) or embedded lists, are encyclopedic content just as paragraph-only articles or sections are. Therefore, all individual items on the list must follow Wikipedia's content policies: the core content policies of Verifiability (through good sources in the item's one or more references), No original research, and Neutral point of view, plus the other content policies as well. Although the format of a list might require less detail per topic, Wikipedia policies and procedures apply equally to both a list of similar things as well as to any related article to which an individual thing on the list might be linked.

It is important to be bold in adding or editing items on a list, but also to balance boldness with being thoughtful, a balance which all content policies are aimed at helping editors achieve. Edits of uncertain quality can be first discussed on the talk page for feedback from other editors.

Besides being useful for such feedback, a talk page discussion is also a good review process for reaching consensus before adding an item that is difficult or contentious, especially those items for which the definition of the topic itself is disputed. Note that, as with other policies and processes mentioned in this section, this process can be used for any type of difficult or contentious encyclopedic content on Wikipedia.

Reaching consensus on the talk page before editing the list itself not only saves time in the long run, but also helps make sure that each item on the list is well referenced and that the list as a whole represents a neutral point of view.

When an item meets the requirements of the Verifiability policy, people reading or editing the list can check an item's reference to see that the information comes from a reliable source. For information to be verifiable, it also means that Wikipedia does not publish original research: its content is determined by information previously published in a good source, rather than the beliefs or experiences of its editors, or even the editor's interpretation based on but beyond what the source actually says. Even if you're sure that an item is relevant to the list's topic, you must find a good source that verifies this knowledge before you add it to the list (although you can suggest it on the talk page), and add that source in a reference next to the item.

In lists that involve living persons, the Biographies of living persons policy applies.

When reliable sources disagree, the policy of keeping a neutral point of view requires that we describe competing views without endorsing any in particular. Simply present what the various sources say, giving each side its due weight through coverage balanced according to the prominence of each viewpoint in the published, reliable sources.

When adding to a stand-alone list with links to other articles, follow the established format when adding your item, and then see if you can a link that item to an article focusing on that item's topic. If so, then consider if the list's format allows room for all the details of competing views in the list item or if those details should only be covered in the linked, main article on the topic. Either way, make sure to add them to the main article if they are not already there.

Category[edit]

You can add a suitable subcategory of Category:Lists at the bottom of the page.

List styles[edit]

There are several ways of presenting lists on Wikipedia.

Line breaks[edit]

cake<br>
cheese<br>
chocolate<br>

renders as:

cake
cheese
chocolate

This method is deprecated as it does not meet web standards and can cause accessibility problems. Instead, use one of the following:

Bulleted lists[edit]

Shortcuts:
Good example
Wikitext HTML Appearance
== Title of list ==
* Example 1
* Example 2
* Example 3
<p><a name="Title_of_list" id="Title_of_list"></a></p>
<h2><span class="mw-headline">Title of list</span></h2>
<ul>
<li>Example 1</li>
<li>Example 2</li>
<li>Example 3</li>
</ul>
Title of list
  • Example 1
  • Example 2
  • Example 3

As a matter of style, list items should be formatted consistently in either sentence case or lower case. They should not have final punctuation unless they consist of complete sentences.

This style is appropriate for long lists, or lists of entries which consist of both a link and explanatory text. Also, it is appropriate when the article already has several titles or subtitles.

The Title provides a direct edit point, if one enables section editing. It also enables the automatic table of contents system to detect the list. It is not required, however.

In particular, do not double-space the lines of the list by leaving blank lines or extra HTML <br> tags after them, as in this example:

Bad example
Wikitext HTML Appearance
== Title of list ==
* Example 1

* Example 2

* Example 3
<p><a name="Title_of_list" id="Title_of_list"></a></p>
<h2><span class="mw-headline">Title of list</span></h2>
<ul>
<li>Example 1</li>
</ul>
<ul>
<li>Example 2</li>
</ul>
<ul>
<li>Example 3</li>
</ul>
Title of list
  • Example 1
  • Example 2
  • Example 3
A
[[File:Example.jpg|thumb|Caption text]]
* Example 1
* Example 2
* Example 3
* Example 4
B
* Example 1
* Example 2
[[File:Example.jpg|thumb|Caption text]]
* Example 3
* Example 4
C
* Example 1
* Example 2
* [[File:Example.jpg|thumb|Caption text]] Example 3
* Example 4

Doing this actually produces three lists with one item each! Notice the rendered HTML in which there are as many <ul> tags as <li> tags. This can adversely affect machine-readability of the content if a continuous list is expected.[1] Moreover in certain web browsers, the extra white-space between one singular list and the next can have a visually jarring effect.

To float pictures to the right of the list, one should put the image markup before the first item in most cases, see the example "A" at right: Inserting the image markup as a separate line within the list (as in example "B") once again will split it into two half-lists.

Should the length of the list items or the topical relevance of said image discourage display at the top corner, consider placing it after the asterisk of the first list-item it illustrates (as in example "C") to avoid breaking continuity of the unordered list (<ul>) element.

Note: Avoid floating images to the left of a list as this disrupts the indentation of the bullet-points, making the hierarchy of list-items more difficult for readers to ascertain.

Unbulleted lists[edit]

Shortcut:

For lists of up to thirty (may increase later) items, without bullets (for example in infobox fields, or to replace lists separated with <br />), {{Plainlist}} or {{Unbulleted list}} should be used. This emits the correct HTML markup, and hides the bullets with CSS.

Wikitext HTML Appearance
== Title of list ==
{{Plainlist|
* Example 1
* Example 2
* Example 3
}}
<p><a name="Title_of_list" id="Title_of_list"></a></p>
<h2><span class="mw-headline">Title of list</span></h2>
<ul>
<li>Example 1</li>
<li>Example 2</li>
<li>Example 3</li>
</ul>
Title of list
  • Example 1
  • Example 2
  • Example 3
== Title of list ==
{{Unbulleted list
| Example 1
| Example 2
| Example 3
}}
<p><a name="Title_of_list" id="Title_of_list"></a></p>
<h2><span class="mw-headline">Title of list</span></h2>
<ul>
<li>Example 1</li>
<li>Example 2</li>
<li>Example 3</li>
</ul>
Title of list
  • Example 1
  • Example 2
  • Example 3

Numbered lists[edit]

Shortcut:

Similar to the above, use a # symbol to obtain a numbered list:

Wikitext HTML Appearance
== Title of list ==
# Example 1
# Example 2
# Example 3
<p><a name="Title_of_list" id="Title_of_list"></a></p>
<h2><span class="mw-headline">Title of list</span></h2>
<ol>
<li>Example 1</li>
<li>Example 2</li>
<li>Example 3</li>
</ol>
Title of list
  1. Example 1
  2. Example 2
  3. Example 3

Blank lines between items of an ordered list will not only cause the same problems as in the previous example, but will also restart the numbering at "1". This cannot be fixed without complex wiki markup (defeating ease-of-editing expectations), so double-spacing should always be avoided in numbered lists.

Other cases[edit]

Experienced editors can use raw html to achieve more complex results, such as ordered lists using indexes other than numbers, and ordered lists not starting from 1.

Wikitext Appearance
<ol type="a">
<li>this</li>
<li>list</li>
<li>uses</li>
<li>letters</li>
<li>as</li>
<li>indexes</li>
</ol>
  1. this
  2. list
  3. uses
  4. letters
  5. as
  6. indexes
<ol start="10">
<li>this</li>
<li>list</li>
<li>starts</li>
<li>from</li>
<li>10</li>
</ol>
  1. this
  2. list
  3. starts
  4. from
  5. 10
<ol type="I" start="50">
<li>this</li>
<li>list</li>
<li>uses</li>
<li>roman</li>
<li>numerals</li>
<li>and</li>
<li>starts</li>
<li>from</li>
<li>50</li>
</ol>
  1. this
  2. list
  3. uses
  4. roman
  5. numerals
  6. and
  7. starts
  8. from
  9. 50

Valid values for the list type are:

  • 1 (default, numbers)
  • a (lowercase latin letters)
  • A (uppercase latin letters)
  • i (lowercase roman numerals)
  • I (uppercase roman numerals)

The start value can be negative, but only if the list uses numbers as indexes. Otherwise, bizarre results are achieved.

Wikitext Appearance
<ol type="a" start="-2">
<li>definitely</li>
<li><b>not</b></li>
<li>a</li>
<li>good</li>
<li>idea!</li>
</ol>
  1. definitely
  2. not
  3. a
  4. good
  5. idea!

Description (definition, association) lists[edit]

Shortcut:

Wikipedia has a special markup for description lists (formerly called definition lists in HTML4 and association lists in early versions of HTML5). A description list contains groups of "terms and definitions, metadata topics and values, questions and answers, or any other groups of name–value data".[2]

There are templates for producing description lists such as glossaries, in ways that provide for richer, more complex content than bare wikimarkup syntax. The basic format of a template-structured description list is:

Wikitext Appearance

{{glossary}}
{{term|name 1}}
{{defn|value 1}}
{{term|name 2}}
{{defn|value 2}}
{{term|name 3}}
{{defn|value 3}}
{{glossary end}}

name 1
value 1
name 2
value 2
name 3
value 3

The content in any {{defn}} can be complex, including multiple paragraphs, block quotations, sub-lists, etc. See Template:Glossary for full documentation.

The simpler, but very functionality-limited and easily broken, basic wikimarkup format is:

Wikitext Appearance
; name 1 : value 1
; name 2 : value 2
; name 3 : value 3
name 1 
value 1
name 2 
value 2
name 3 
value 3

An alternative source layout is to put the name on a separate line straight after the term, like so:

Wikitext Appearance
; name 1
: This is the value associated with the first name and may be quite long, but must be one unbroken line in the source.
; name 2
: This is the value associated with the second name, which may also be long.
name 1
This is the value associated with the first term and may be quite long, but must be one unbroken line in the source.
name 2
This is the value associated with the second term, which may also be long.

This still keeps the names and values within a single description list, and the alternation of typically short names and longer values makes the separate components easy to spot while editing. The resulting layout and HTML are identical to that generated by the single-line syntax.

A major weakness of both variants of ;-and-: markup is that they are easily broken by later editors attempting to create multi-line values. Use of template-structured formatting resolves that problem.

Use structured or description list format instead of other, made-up formats, as they may not fit reader and editor expectations, hamper reusability of Wikipedia content, make automated processing more difficult, or introduce usability and accessibility problems.

As with unordered (bulleted) lists, items in description lists should not be double-spaced, as it causes each entry to be its own bogus "list" in the output, obviating the point of putting the entries in list markup to begin with.

In some cases tables are better-suited to associating content than description lists.

Note that when colons are used for indentation, in articles or on talk pages, they too are rendered in HTML as description lists. It is preferable to use Template:Indent or one of its variants, especially in articles.

Tables[edit]

Although the use of tables to display lists is discouraged—because they provide low-quality accessibility and have a more complex notation that hinders editing—there are some instances where they can be useful, such as when three or more columns are required. See Wikipedia:When to use tables.

Horizontal lists[edit]

Shortcut:

In situations such as infoboxes, a single-line list may be useful—in this case:

List type
entry one, entry two, entry three
Heading 1 Heading 2
List with commas Entry 1, entry 2, entry 3
List with {{Flatlist}}
  • Entry 1
  • entry 2
  • entry 3

Note the capitalization of only the first word in this list (but words that are normally capitalized would still be capitalized). This applies regardless of the separator used between the list type and the entries themselves—whether it is a comma (as in the first example above), or an infobox divider (as in the second example above).

Timelines[edit]

Shortcuts:

For lists of dated events, or timelines, use one instance of {{Timeline-event}} per event, thus:

* {{Timeline-event|date={{Start date|1904|11|18|df=y}}|event=A thing happened}}
* {{Timeline-event|date={{Start date|1905}}|event=Not much happened}}
* {{Timeline-event|date={{Start date|1906|01|21}}|event=Something else happened}}

to render as:

  • 18 November 1904 (1904-11-18) – A thing happened
  • 1905 (1905) – Not much happened
  • January 21, 1906 (1906-01-21) – Something else happened

(note optional df=y (date first) parameter – date formatting should be consistent within individual articles).

Boilerplate text[edit]

Directly before an incomplete list, insert {{expand list}}, which will substitute the following onto the page:

Several topic-specific variations of this template are also available within Category:List notification templates. Only one of {{expand list}} or its variations should be added, unless the topic is significantly related to more than one of the subcategories. Do not add both {{expand list}} AND a variation to any list.

Bulleted and numbered lists[edit]

  • Do not use lists if a passage is read easily as plain paragraphs.
  • Use proper wikimarkup- or template-based list code (see WP:Manual of Style/Lists and Help:List).
  • Do not leave blank lines between items in a bulleted or numbered list unless there is a reason to do so, since this causes the Wiki software to interpret each item as beginning a new list.
  • Use numbers rather than bullets only if any of the following apply:
    • A need to refer to the elements by number may arise.
    • The sequence of the items is critical.
    • The numbering has some independent meaning, for example in a listing of musical tracks.
  • Use the same grammatical form for all elements in a list, and do not mix sentences and sentence fragments as elements.
    • When the elements are complete sentences, each one is formatted with sentence case (i.e. the initial letter is capitalized) and a final period.
    • When the elements are sentence fragments, the list is typically introduced by a lead fragment ending with a colon. When these elements are titles of works, they retain the original capitalization of the titles. Other elements are formatted consistently in either sentence case or lower case. No final punctuation is used.

Pro and con lists[edit]

These are lists of arguments for and against a particular contention or position. They include lists of Advantages and disadvantages of a technology or proposal (such as Wi-Fi) and lists of Criticisms and defenses of a political position or other view, such as libertarianism or evolution. Pro and con lists can encapsulate or bracket neutrality problems in an article by creating separate spaces in which different points of view can be expressed. An alternative method is to thread different points of view into running prose.

Either method needs careful judgment as to whether and how it should be used. In particular, pro and con lists can fragment the presentation of facts, create a binary structure where a more nuanced treatment of the spectrum of facts is preferable, encourage oversimplification, and require readers to jump back and forth between the two sides of the list.

See also[edit]

Notes[edit]

  1. ^ Blank lines cause particular problems for users of screen readers. The badly formatted example above is read out loud like this: "List of 1 items: Example 1, list end. List of 1 items: Example 2, list end. List of 1 items: Example 3, list end." Improper formatting can more than triple the length of time it takes to read the list.
  2. ^ W3C (5 April 2011), HTML5: A Vocabulary and Associated APIs for HTML and XHTML, W3C Working Draft .