WP:UBLIST

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

List articles
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 Stand-alone lists style guideline.

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 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
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
Lists have three main purposes:

Information
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
Lists contain internally linked terms (i.e., wikilinks) and thus in aggregate serve 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
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 primarily of red links) should be in project or user space, not the main space.

Lists and categories
Redundancy of lists and categories is beneficial because the two categories work together; the principle is covered in the guideline 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
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), 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. When adjective like "individual", "complete," "famous" and "notable" are not necessary to describe the nature and scope of the list and to distinguish it from other lists, as with List of diamonds, List of Labrador Retrievers, or List of minor planets, they should not be used. In other cases, such as List of famous gemstones, List of individual dogs, or List of notable asteroids, such adjectives are used to clearly describe the nature and scope of the article and to distinguish them from other articles.

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

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).

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

Organization
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.

Listed items
Lists, whether they are embedded lists or stand-alone lists, are encyclopedic content as are paragraphs and articles, and they are equally subject to Wikipedia's content policies such as Verifiability, No original research, Neutral point of view, and others.

Difficult or contentious subjects for which the definition of the topic itself is disputed should be discussed on the talk page in order to attain consensus and to ensure that each item to be included on the list is adequately referenced and that the page on which the list appears as a whole represents a neutral point of view.

The principle of Neutral Point of View requires that we describe competing views without endorsing any one in particular. No original research applies equally to a list of like things as it does for the content article on each individual thing listed.

The verifiability policy states that material challenged or likely to be challenged must be attributed to a reliable published source. Inclusion of material on a list should be based on what reliable sources say, not on what the editor interprets the source to be saying. In lists that involve living persons, the Biographies of living persons policy applies.

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

List styles
There are several ways of presenting lists on Wikipedia.

Line breaks
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
{| class="wikitable" ! scope="col" | Wikitext ! scope="col" | HTML ! scope="col" | Appearance
 * +Good example
 * - style="vertical-align:top;"
 * 

Title of list
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.
 * Example 1
 * Example 2
 * Example 3
 * style="white-space:nowrap; padding:1em;" |  Title of list
 * Example 1
 * Example 2
 * Example 3
 * }
 * }

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  tags after them, as in this example: {| class="wikitable" ! scope="col" | Wikitext ! scope="col" | HTML ! scope="col" | Appearance
 * +Bad example
 * - style="vertical-align:top;"
 * 

Title of list

 * Example 1


 * Example 2


 * Example 3
 * style="white-space:nowrap; padding:1em;" |  Title of list
 * Example 1
 * Example 1


 * Example 2


 * Example 3
 * }

Doing this actually produces three lists with one item each! Notice the rendered HTML in which there are as many &lt;ul&gt; tags as &lt;li&gt; tags. This can adversely affect machine-readability of the content if a continuous list is expected. 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 () 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
For lists of up to thirty (may increase later) items, without bullets (for example in infobox fields, or to replace lists separated with ), Plainlist or Unbulleted list should be used. This emits the correct HTML markup, and hides the bullets with CSS.

{| class="wikitable" ! Wikitext ! HTML ! Appearance
 * - style="vertical-align:top;"
 * 

Title of list
Example 1

Example 2

Example 3

Example 1
 * style="white-space:nowrap; padding:1em;" |  Title of list
 * style="white-space:nowrap; padding:1em;" |  Title of list

Example 2

Example 3


 * - style="vertical-align:top;"
 * 

Title of list
Example 1

Example 2

Example 3 Example 1
 * style="white-space:nowrap; padding:1em;" |  Title of list
 * style="white-space:nowrap; padding:1em;" |  Title of list

Example 2

Example 3
 * }

Numbered lists
Similar to the above, use a # symbol to obtain a numbered list: {| class="wikitable" ! Wikitext ! HTML ! Appearance

Title of list
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.
 * 1) Example 1
 * 2) Example 2
 * 3) Example 3
 * style="white-space:nowrap; padding:1em;" |  Title of list
 * 1) Example 1
 * 2) Example 2
 * 3) Example 3
 * }
 * }

Description (definition, association) lists
Wikipedia has a special markup for (formerly called ' in HTML4 and ' 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".

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  is:

See Template:Gloss for full documentation.

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

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

This still keeps the names and values within a single definition 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. Use this definition list format instead of other ones like

or

As with unordered (bulleted) lists, items in definition 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 definition lists.

Tables
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 When to use tables.

Comma-separated lists
In situations such as info boxes, a comma-separated list that is outside the context of a sentence may be useful—in this case, a format such as: ; List type: entry one, entry two, entry three is most appropriate—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 colon (as in the first example above), or even an infobox divider (as in the second example above).

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

to render as:



(note optional  (date first) parameter - date formatting should be consistent within individual articles).

Boilerplate text
Directly before an incomplete list, insert, which will substitute the following onto the page:

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

Bulleted and numbered lists

 * 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:
 * a need to refer to the elements by number may arise;
 * the sequence of the items is critical;
 * or 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. Each element should end with a semicolon or comma (whichever you would use if the items were not formatted as a list), with a period instead for the last element. Alternatively (especially when the elements are short), no final punctuation is used at all.

Pro and con lists
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.