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Wikipedia:Lead section

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This guideline is a part of the English Wikipedia's Manual of Style. Use common sense in applying it; it will have occasional exceptions. Please ensure that any edits to this page reflect consensus.

Shortcuts: WP:LEAD WP:LS

This page in a nutshell: The lead should define the topic and summarize the body of the article with appropriate weight.

The lead section (also known as the introduction or the lead) of a Wikipedia article is the section before the table of contents and first heading. The lead serves both as an introduction to the article and as a summary of the important aspects of the subject of the article.

The lead should be able to stand alone as a concise overview of the article. It should define the topic, establish context, explain why the subject is interesting or notable, and summarize the most important points—including any notable controversies. The emphasis given to material in the lead should roughly reflect its importance to the topic, according to reliable, published sources, and the notability of the article's subject should usually be established in the first sentence.

While consideration should be given to creating interest in reading more of the article, the lead nonetheless should not "tease" the reader by hinting at—but not explaining—important facts that will appear later in the article. The lead should contain no more than four paragraphs, should be carefully sourced as appropriate, and should be written in a clear, accessible style to invite a reading of the full article.

Elements of the lead

As explained in more detail below, the lead section may contain optional elements presented in the following order: disambiguation links (dablinks), maintenance tags, infoboxes, images, navigational boxes (navigational templates), introductory text, and table of contents, moving to the heading of the first section.

Correct Structure of Lead Section
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{{Rocket Infobox|name=...}}
[[File:TypicalRocket.gif|...|A typical rocket]] or {{Rocket Navigation}}
A '''rocket''' is a...
[table of contents]
== First section ==

• Disambiguation links should be the first elements of the page, before any maintenance tags, infobox or image; if a reader has reached the wrong page, they typically want to know that first. Text-only browsers and screen readers present the page sequentially. A "for topics of the same name ..." disambiguation link is sometimes put at the beginning of an article to link to another article discussing another meaning of the article title. Do not make this initial link a section. In such cases, the line should be italicized and indented using templates. A horizontal line should not be placed under this line. See also Wikipedia:Hatnote.
• The maintenance tags should be below the disambiguation links. These tags inform the reader about the general quality of the article, and should be presented to the user before the article itself.
• Infoboxes contain summary information or an overview relating to the subject of the article, and therefore should be put before any text (though in actuality they will generally appear to the side of the text of the lead). The primary difference between an infobox and a navigational box is the presence of parameters: a navigational box is exactly the same in all articles of the same topic, while an infobox has different contents in each article.
• Images. An image's caption is part of the article text. If the article has disambiguation links (dablinks), then the introductory image should appear just before the introductory text. Otherwise a screen reader would first read the image's caption, which is part of the article's contents, then "jump" outside the article to read the dablink, and then return to the lead section, which is an illogical sequence.
• Navigational templates (also called "navigational boxes") are a collection of links used in multiple related articles to facilitate navigation between those articles. Vertical navigational boxes, sometimes called "sidebars", and horizontal navigational boxes are sometimes placed in the lead, especially when no infobox is present. If an infobox is present, the navigation sidebar may be moved to either the top or bottom of any other section in the article.
• Link to parent article. In the event that the article is a sub-article (or similarly linked article), that relationship should be clearly outlined just before the opening sentence. For example, Meccan boycott of the Hashemites begins with an indented line stating:

  This is a sub-article to Muhammad before Medina.

• Introductory text. As explained in more detail at Wikipedia:Lead section#Introductory text, all but the shortest articles should start with introductory text (the "lead"). The lead should establish significance, include mention of notable criticism or controversies, and be written in a way that makes readers want to know more. The appropriate length of the lead depends on that of the article, but should be no more than four paragraphs. The lead itself has no heading and, on pages with more than three headings, automatically appears above the table of contents, if present. See also Wikipedia:Guide to writing better articles#Lead section.
• The table of contents (TOC) automatically appears on pages with more than three headings. Avoid floating the table of contents if possible, as it breaks the standard look of pages. If you must use a floated TOC, put it below the lead section in the wiki markup for consistency. Users of screen readers expect the table of contents to follow the introductory text; they will also miss any text placed between the TOC and the first heading.

Citations

The lead must conform to verifiability and other policies. The verifiability policy advises that material that is challenged or likely to be challenged, and quotations, should be cited. Because the lead will usually repeat information also in the body, editors should balance the desire to avoid redundant citations in the lead with the desire to aid readers in locating sources for challengeable material. Leads are usually written at a greater level of generality than the body, and information in the lead section of non-controversial subjects is less likely to be challenged and less likely to require a source; there is not, however, an exception to citation requirements specific to leads. The necessity for citations in a lead should be determined on a case-by-case basis by editorial consensus. Complex, current, or controversial subjects may require many citations; others, few or none. Contentious material about living persons must be cited every time, regardless of the level of generality.

Introductory text

Provide an accessible overview

The lead section should briefly summarize the most important points covered in an article in such a way that it can stand on its own as a concise version of the article. It is even more important here than for the rest of the article that the text be accessible. Consideration should be given to creating interest in reading the whole article. (See news style and summary style.) This allows editors to avoid lengthy paragraphs and over-specific descriptions, because the reader will know that greater detail is saved for the body of the article.

In general, specialized terminology and symbols should be avoided in an introduction. Mathematical equations and formulas should not be used except in mathematics articles. Where uncommon terms are essential to describing the subject, they should be placed in context, briefly defined, and linked. The subject should be placed in a context with which many readers could be expected to be familiar. For example, rather than giving the latitude and longitude of a town, it is better to state that it is the suburb of some city, or perhaps that it provides services for the farm country of xyz county. Readers should not be dropped into the middle of the subject from the first word; they should be eased into it.

Relative emphasis

In general, the relative emphasis given to material in the lead should reflect its relative importance to the subject according to reliable sources. Significant information should not appear in the lead if it is not covered in the remainder of the article, although specific facts, such as birthdates, titles, or scientific designations will often appear in the lead only, as may certain quotations. This should not be taken to exclude information from the lead, but to include it in both the lead and body: in a well-constructed article, the relative emphasis given to information in the lead will be reflected in the rest of the text. Do not tease the reader by hinting at startling facts without describing them.

Opening paragraph

The first paragraph of the introductory text needs to unambiguously define the topic for the reader, without being overly specific. It should establish the context in which the topic is being considered, by supplying the set of circumstances or facts that surround it. If appropriate, it should give the location and time context. Also, it must establish the boundaries of the content of the article (for example List of environmental issues is only about the effects of human activity).

First sentence

The article should begin with a declarative sentence, answering two questions for the nonspecialist reader: "What (or who) is the subject?" and "Why is this subject notable?"

• If possible, the page title should be the subject of the first sentence. However, if the article title is merely descriptive—such as Electrical characteristics of dynamic loudspeakers—the title does not need to appear verbatim in the main text. Similarly, where an article title is of the type "List of ...", a clearer and more informative introduction to the list is better than verbatim repetition of the title.
• When the page title is used as the subject of the first sentence, it may appear in a slightly different form, and it may include variations, including synonyms. Similarly, if the title has a parenthetical disambiguator, the disambiguator should be omitted in the text.
• If its subject is amenable to definition, then the first sentence should give a concise definition: where possible, one that puts the article in context for the nonspecialist. Similarly, if the subject is a specialised term, provide the context as early as possible.
• If the article is about a fictional character or place, say so.
• If the page is a list, do not introduce the list as "This is a list of X" or "This list of Xs...". (See Format of the first sentence below).

Format of the first sentence

Most commonly, the article's subject is stated as early as possible in the first sentence, and placed in boldface:

The electron is a subatomic particle that carries a negative electric charge.

Only the first occurrence of this word or term is placed in boldface.

Title variants

If the page title is descriptive it does not need to appear verbatim in the main text, and even if it does it should not be in boldface. So, for example, Electrical characteristics of dynamic loudspeakers begins with:

A dynamic loudspeaker driver's chief electrical characteristic is its electrical impedance versus frequency.

Simple descriptions such as "History of the United States" or "Timeline of prehistoric Scotland" should be bold.

Proper names and titles

If the subject of the page is normally italicized (for example, a work of art, literature, album, or ship) then its first mention should be both bold and italic text; if it is usually surrounded by quotation marks, the title should be bold but the quotation marks should not:

Las Meninas (Spanish for The Maids of Honour) is a 1656 painting by Diego Velázquez, ...

"Yesterday" is a pop song originally recorded by The Beatles for their 1965 album Help!.

Abbreviations and synonyms

If the subject of the page has a common abbreviation or more than one name, the abbreviation (in parentheses) and each additional name should be in boldface on its first appearance.

Sodium hydroxide (NaOH), also known as lye and caustic soda, is ...

Foreign language

Do not boldface foreign names not normally used in English, or variations included only to show etymology. Foreign names (including transcriptions) that use the Roman alphabet should be italicized if they are not bolded; those written in other alphabets (such as Cyrillic) should not.

Chernivtsi Oblast (Ukrainian: Чернівецька область, Chernivets’ka oblast’) is an oblast (province) in western Ukraine, bordering on Romania and Moldova.

Inuit (plural; the singular Inuk means "man" or "person") is a general term for a group of culturally similar indigenous peoples inhabiting the Arctic regions . . .

Links

Use as few links as possible before and in the bolded title. Thereafter, words used in a title may be linked to provide more detail:

Arugam Bay is a bay situated on the Indian Ocean in the dry zone of Sri Lanka's southeast coast.

Biographies

When writing about controversies in the lead of the biography of a living person, notable material should neither be suppressed nor allowed to overwhelm: always pay scrupulous attention to reliable sources. Write clinically, and let the facts speak for themselves.

Well-publicized recent events affecting an article subject, whether controversial or not, should be kept in historical perspective. What is most recent is not necessarily what is most notable: new information should be carefully balanced against old, with due weight accorded to each. When an article subject dies, the lead does not need to be radically reworked. Unless the cause of death is itself a reason for notability, a single sentence describing it is usually sufficient.

Alternative names

Although Wikipedia's naming convention guidelines recommend the use of English, there are instances where the subject of an article is best-known in English-speaking sources by its non-English name. In this case, the non-English title may be appropriate for the article. When the subject is best known by an English title, its alternative names may be included; however, the editor needs to balance the desire to maximize the information available to the reader with the need to maintain readability.

Usage in first sentence

In articles about places, people, literary and artistic works, scientific principles and concepts, and other subjects, the title can be followed in the first line by one or two alternative names in parentheses. The following are examples of names that may be included parenthetically, but this is not mandatory, and inclusion should reflect consensus.

• Archaic names, including names used before the standardization of English orthography should be clearly marked as such, i.e., (archaic: name1).
• Relevant foreign language names, such as in an article on a person who does not herself write her name in English, are encouraged.

Separate section usage

Alternatively, if there are more than two alternative names, these names can be moved to and explained in a "Names" or "Etymology" section; it is recommended that this be done if there are at least three alternate names, or there is something notable about the names themselves. Once such a section or paragraph is created, the alternative English or foreign names should not be moved back to the first line. As an exception, a local official name different from a widely accepted English name should be retained in the lead "(Foreign language: Local name; other names exist)".

Stubs

Where the article is a stub, a lead may not be necessary at all. Wikipedia encourages expanding stubs, but if reliably sourced information is not available, this may not be possible. Once an article has been sufficiently expanded, generally to around 400 or 500 words, editors should consider introducing section headings.

Length

The appropriate length of the lead section depends on the total length of the article. As a general guideline, the lead should be no longer than four paragraphs. The following suggestion may be useful:

Lead sections that reflect or expand on sections in other articles are discussed at Summary style. Journalistic conventions for lead sections are discussed at News style.

Editing the lead section

Editing the lead section can be cumbersome in long articles, because by default there is no edit link.

Registered users can override this default via:

• checkbox on Special:Preferences > Gadgets > User interface gadgets: editing called "Add an [edit] link for the lead section of a page".
• checkbox on Special:Preferences > Editing called "Enable section editing by right-clicking on section titles" (requires JavaScript)

All users can use the following:

• Another way to work around this is by clicking "edit" for any section, and in the resulting URL, replace the trailing &section=n with &section=0.
• A more cumbersome alternative is to open the entire article in the editing window by clicking on "edit this page". However, this method increases the risk of edit conflicts in popular articles, and may cause problems in some web browsers if the page being edited is too large. There are also some user-written scripts that enable you to edit section 0.

Cleanup

For a list of template messages related to the clean-up of lead sections, see Wikipedia:Template messages/Cleanup#Introduction. Editors are encouraged to improve leads rather than simply tagging them.

See also

• Wikipedia:Accessibility
• Wikipedia:Lead section TT first sentence content
• Wikipedia:Lead section TT first sentence format
• Wikipedia:Lead section TT text
• Wikipedia:WikiProject Introductions
• Wikipedia:Writing better articles
• Wikipedia's Good definition policy

Notes