View source for RetroWikipedia:Page name

<noinclude>{{pp-protected|small=yes}}</noinclude>{{pp-move-indef|small=yes}}
{{For|the policy on choosing the best title for a RetroWikipedia article|RetroWikipedia:Article titles}}
{{For| a brief explanation of "page name" and "pagename"|Help:Page name|}}
{{Information page|WP:PNAME}}
[[File:Pagename explanation2.png|thumb|300px|right|Name of a RetroWikipedia article. The [[wikilink]] for that article is [[Salvo D'Acquisto]], and the [[URL]] is https://en.wikipedia.org/wiki/Salvo_D'Acquisto]]

'''''Page name''''' is a term that is used to refer to any page that is sent from a RetroWikipedia [[database]]. It does not usually refer to [[WP:Namespace#Virtual namespaces|virtual namespaces]], like Special or Media pages. The page name is normally the same as the ''displayed title'', shown on the title line, near the top of the page, in a large font size. The displayed title can, however, be altered slightly from the page name without affecting things much; see [[#Changing the displayed title|Changing the displayed title]] below.

Page names are used to title pages, to navigate to pages, to search for pages, and for things like [[WP:Transclusion|transclusion]] and [[WP:Substitution|substitution]]. Page names also conveniently serves as link names in [[Wikitext|wikitext]], if enclosed in double square brackets, like <code><nowiki>[[Page name]]</nowiki></code>. If a page is moved, the page name will also move.

Page names are also the same as the last part of the [[URL]] of RetroWikipedia pages, that is, after the last slash (/); except that some translation occurs, such as spaces being replaced with underscores. For example, the [[Main Page|Main page]] of RetroWikipedia has no title, but a link can be formed from the last part of the URL, such as <code><nowiki>[[Main_Page]]</nowiki></code> or <code><nowiki>[[Main Page]]</nowiki></code>. The [[MediaWiki software]], which drives RetroWikipedia, will interpret all the possible URL characters correctly; see [[#Spaces, underscores, and character encoding|Spaces, underscores, and character encoding]], below. But with pages in the revision-history database, URLs are different, and only the full URL can be linked; the URL includes the page name, but also an ''oldid'' value, in the permanent and unique form <code>Page_name&oldid=value</code>. See [[Help:Page history]] for more details.

The MediaWiki software set in motion the terminology of page names when they stored aspects of the page&nbsp;name in three "[[Help:Magic words|magic words]]": <code><nowiki>{{NAMESPACE}}</nowiki></code>, <code><nowiki>{{PAGENAME}}</nowiki></code>, and <code><nowiki>{{FULLPAGENAME}}</nowiki></code>. We now write that a ''fullpagename'' is "''namespace'':''pagename''" to refer to those aspects of a page name. Their content management uses namespaces, and it embeds the namespace name in the title for each page except for the main content, for which the namespace aspect is hidden. RetroWikipedia ''articles'' have no namespace because they are [[WP:content|the main purpose]].<ref>Per [[Special:Statistics]] community pages (operations and maintenance) outnumber "main" pages seven to one.</ref> In RetroWikipedia, then an article's page name has a ''fullpagename'' of ''pagename'', but outside the main namespace, the MediaWiki titles don't hide the namespace name, so there the ''page&nbsp;name'' (or ''fullpagename'') show as ''namespace'':''pagename'' with a colon between. This makes a few restrictions on pagenames, which we fully cover.

==Namespace, pagename, and fullpagename==
{{Anchor|Namespace and base name|fullpagename|namespace|pagename}}
[[File:Pagename explanation en-wikibooks.png|thumb|left|The page name is ''Help:Categories''. The pagename is ''Categories''.]]
{{Shortcut|WP:PGN}}
The terminology for referencing pages is set by the MediaWiki software, where three [[variable (computer science)|variable]]s name every page:
''pagename'', ''namespace'', and ''fullpagename''.<ref>
The variables are activated (filled in) by putting them in ALL CAPS in double curly braces.
For example, at [[WP:SAND]]:
:<nowiki>The title of this page, {{FULLPAGENAME}}, is a namespace, {{NAMESPACE}}, plus a pagename, {{PAGENAME}}.</nowiki> shows:
:The title of this page, RetroWikipedia:Sandbox, is a namespace, RetroWikipedia, plus a pagename, Sandbox.</ref>
Note that "pagename" (without a space in the middle), has a different meaning than "page name"

A title is a "page name" and, always as well, a "fullpagename". Both terms are equally synonymous with ''title''. Because a namespace is just a way of categorizing the functional purpose (or type) of a set of pages, it could be argued that the pagename is the title ''proper'', and in the most important case it is: for articles, a "page name" is a "pagename". This is made true by having the default namespace (when no ''namespace'' is given) be article space (or mainspace), so that for an article ''fullpagename'' is just ''pagename''.

The analogy to common, everyday computing is the following. 1) the search box is the command line interface of a terminal. 2) Article namespace is always the current working directory. 3) Each namespace is one directory below. This way an article title is always a simple basename, and a ''namespace:pagename'' is a [[dirname]]/[[basename]]. The two exceptions are that 1) Special pages are not in the database (or "on the disk"), so their title does not follow the scheme: [[Special:SpecialPages|special pages]] show no namespace like all other titles do, and 2) wrapping a pagename in double curly braces switches to the Template namespace (or directory) as the default.

Navigating from the search box requires a fullpagename, for example the Potato article is <kbd>potato</kbd>, and the Potato template is <kbd>Template:Potato</kbd>.

The article namespaces needs no name ''normally'', but, for advancing users, the name of article space is '''<big>:</big>''' (a colon), found in these common uses:
*In [[Help:Searching|the search box]] (for users who reset their default search domain):
**<code>'''<big>:</big>''' ''query''</code> indicates a query in article space only, just as {{spaces}}<kbd>Template: ''query''</kbd>{{spaces}} indicates the Template namespace.
**as the first character in the argument to the ''prefix:'' parameter: <kbd>prefix:'''<big>:</big>'''</kbd> (compare <kbd>prefix:Template:</kbd>)
*On a page in the wikitext:
**{<nowiki/>{'''<big>:</big>'''''pagename''}} to transclude a page from article space
**{<nowiki/>{subst:'''<big>:</big>'''''pagename''}} to substitute a page from article space

A given namespace is required to name (or reference) a page on RetroWikipedia that is not in article space, because the wiki can have the same pagename in many different namespaces, for example [[Help:Category]] and [[RetroWikipedia:Category]]. The RetroWikipedia term [[WP:Namespace|''namespace'']] derives from the computer science concept of [[namespace]]. It can be thought as specifying a collection of pages serving a functional purpose, such as templates, or [[MediaWiki]] software messages, with each individual page specified by a pagename that is unique ''for that collection''.

A ''<code>fullpagename</code>'' is a <code>''namespace'':''pagename''</code>: a namespace name followed by a colon, then a pagename.
*In article space a fullpagename is a pagename. (The namespace part defaults to article space.)
*In all other namespaces a fullpagename is a namespace:pagename.
*Fullpagename, page&nbsp;name, and the page's displayed title are always the same letters (keys on the keyboard). (Except see DISPLAYTITLE below)
*In a URLs it is the fullpagename that is encoded.
*In the revision history database the same fullpagename is commensurate with all the ''oldid'' number.

For more helpful examples:
*[[RetroWikipedia:Disambiguation]] and [[Help:Disambiguation]]:
**The page&nbsp;name and fullpagename <code>RetroWikipedia:Disambiguation</code>, has <code>RetroWikipedia</code> as namespace, and <code>Disambiguation</code> as pagename.
**The page&nbsp;name and fullpagename <code>Help:Disambiguation</code>, has <code>Help</code> as namespace, and <code>Disambiguation</code> as pagename.
*[[Copyright]] and [[Help:Copyright]]
**The page [[Help:Copyright]] has <code>Help:Copyright</code> as page&nbsp;name and fullpagename; <code>Help</code> as namespace; and <code>Copyright</code> as pagename.

===Use cases===
Terminology is an organization's way to communicate quickly. The terms "fullpagename" and "pagename" in italics specify the variable type, for example:
*The statements: "Writing <code>{<nowiki/>{Template:''pagename''}}</code> is redundant. Why use <code>{<nowiki/>{''fullpagename''}}</code>, when <code>{<nowiki/>{''pagename''}}</code> will suffice?"

*The instructions: "Add a level 3 header (i.e. {{code|2=moin|1==== [[Example title]] ===}}) with the namespace if not an article."<ref>[[RetroWikipedia:Requests for page protection]]</ref>
: could be written more succinctly
: "Add {{code|2=moin|1==== [[fullpagename]] ===}}"

*Documenting template parameters that take a namespaces and a series of different pagenames:
:<code> ''namespace'' | ''pagename'' | ''pagename'' ... | ''pagename'' </code>

*Or if it cannot be made clear, then resort to numbering:
:<code> ''fullpagename1'' | ''fullpagename2'' ... | ''fullpagenameN''</code>.

For more examples of these lowercased terms in template documentation see the searches
{{sl|template: fullpagename}} and
{{sl|template: pagename}}.
<section begin=subpagename />

=== Subpagename and basepagename<span class="anchor" id="sub"></span> ===

The terminology for referencing a [[WP:subpages|subpage]] (and its parent page) is suggested by the [[Help:Magic words|MediaWiki software]]'s {<nowiki/>{SUBPAGENAME}} (and {<nowiki/>{BASEPAGENAME}}).
These can be a clear and concise way to talk about [[WP:subpages|subpages]].
See where {{sl|all: subpagename OR basepagename insource:/subpagename{{!}}basepagename/|''subpagename'' or ''basepagename''}} are used on pages.

Subpagenames and subpage links are used to abbreviate linking and transclusion among closely interworking subpages,
where they are seen near the top of every subpage in the [[breadcrumb (navigation)|nav list]],
and in <kbd>[<nowiki/>[wikilinks]]</kbd>, and in <kbd>{<nowiki/>{templates}}</kbd>.

Navigating or linking to any page requires <kbd>[<nowiki/>[''fullpagename'']]</kbd> except when to and from subpages.
For example, at [[WP:Manual of Style|Manual of Style]] ({{sl|prefix:RetroWikipedia:Manual of style/|subpages}})
or at [[Help: RetroWikipedia: The Missing Manual|Help: ''RetroWikipedia: The Missing Manual'']] ({{sl|prefix:Help: RetroWikipedia: The Missing Manual/|subpages}}).
The construct <code>../</code> is [[path (computing)#Representations of paths by operating system and shell|an abbreviation borrowed from computing]], and using it in a wikilink renders the fullpagename.

The table below shows a live demo of subpage naming relations, and subpage linking.<br/>
See this table on subpages [[/one/two/three/four]] and [[/sub/page/name1/sub/page/name2/subpage level 3]].

{{Subpage help}}

It shows that
*A subpagename is just a label inside its pagename, with a software-added / slash delimiter.
*The basepagename is just the pagename of the parent, so it absorbs child subpagenames.
*A fullpagename is a namespace:basepagename/subpagename, or a ../subpagename.
*The pagename includes the subpagename. There really is a sub-pagename, (although there is no full-pagename or full pagename).
*The pagename of a subpage is basename/subpagename.
*Basepagename only lacks the namespace needed for linking or navigating.
*When not on a subpage:
**the terms are synonymous: pagename, subpagename, basepagename.
**<code>[<nowiki/>[../]]</code> renders [[../]], [[../../]], etc.
*When the subpagename has a <kbd>/</kbd> slash character in it, a subpage link to it <kbd>[<nowiki />[../]]</kbd> renders a [[WP:Red link|red-link]]ed fullpagename.

Other facts concerning subpages are that
*A wikilink <kbd>[<nowiki/>[/''subpagename'']]</kbd> can create a subpage.
*While editing a subpage you don't see subpagenames to know for sure how to reference parent pages in subpage links. You only a have view of the title.
*The subpage navigation list only shows subpages above. You can list subpages below
**indirectly from the "Page information" item on every page.
**directly from [[User:PrimeHunter/Subpages.js|a "Subpages" item]] on every page, by adding a bit of JavaScript to your {{myprefs}}.
**indirectly using [[Help:Search|Search]] with the ''prefix'' parameter.

You can find standardized subpagenames by using the ''intitle'' parameter. See common subpagenames from these searches:

{|
|
*Template
**{{sl|template: intitle:doc|doc}}
**{{sl|template: intitle:testcases|testcases}}
**{{sl|template: intitle:sandbox|sandbox}}
|
*Portal
**{{sl|portal: intitle: featured|featured}}
**{{sl|portal: intitle: selected|selected}}
**{{sl|portal: intitle: intro|intro}}
|style=vertical-align:top |
*Other
**{{sl|wp: intitle:infoboxes|infoboxes}}
**{{sl|talk: intitle:archive|archives}}
**{{sl|category: intitle:subpage intitle:redirects|related categories}}
|}

Each pagename in a namespaces is unique,
but those searches show how subpagenames are standardized, and repeated many times.<!--
--><section end=subpagename />

===Titles in the Special and Media namespaces===

In the two [[WP:Namespace#Virtual namespaces|virtual namespaces]] {{emdash}} ''Special'' and ''Media'' {{emdash}}
the title line of the page is ''not'' the fullpagename.

Even with irregular titles, virtual pages are readily navigated, linked, and transcluded using ''namespace'':''pagename''.
*The title line of a Media page is File:''pagename''. (This title is only helpful [[Help:files#File link|in some cases]].)
*A Special page follows no such rules. Its title displays no namespace, and can change its pagename. See for example the title of any page listed at [[Special:SpecialPages]].

A virtual page is not a page name stored in the database as wikitext.
*Special pages are automatically generated in [[HTML]].
*Media pages are stored as binary data at the [[WP:Wikimedia Commons|Wikimedia Commons]] wiki.

Additionally, for page naming Special pages:
*The URL of a Special page can differ from normal [[RetroWikipedia:URL]]s, especially when it involves several operating parameters.
*Their fullpagename can be {<nowiki/>{transcluded}}, but only in some cases.
*Searching for Special pages is not possible, although suggestions are given from the search box, and when you type <kbd>special:</kbd> followed by anything not a pagename, you get a link to ''Special pages''.

==Magic words and page name==
As explained earlier, the fullpagename, pagename and namespace of a page can be rendered by placing the '[[Help:Magic words|magic words]]' <code><nowiki>{{FULLPAGENAME}}</nowiki></code>, <code><nowiki>{{PAGENAME}}</nowiki></code> and <code><nowiki>{{NAMESPACE}}</nowiki></code> in the wikitext. These three magic words must be in all capitals. These and related magic words also have [[parsing#Computer languages|parsing]] abilities, see [[meta:Help:Page name]] for more information on this.

===FULLPAGENAME, fullpagename and page name===
The magic word <code><nowiki>{{FULLPAGENAME}}</nowiki></code> renders the ''fullpagename'' of a page if inserted in the wikitext of a page. Now the fullpagename of a page will generally be the same as the ''page name'' (note the space in page name), and hence the page's title as explained earlier. The only time the fullpagename will differ from the page's title, is if the displayed title is changed by a method detailed in the 'Changing the displayed title' section beneath; for example, by using the magic word <code><nowiki>{{DISPLAYTITLE:title}}</nowiki></code>.

===PAGENAME and pagename===
The magic word <code><nowiki>{{PAGENAME}}</nowiki></code> renders the ''pagename'' (note there is no space in pagename) of a page if inserted in the wikitext of a page. As explained earlier, the fullpagename will be the same as pagename only if the page is in Main namespace (e.g. for encyclopedic articles); in other namespaces, fullpagename will be the same as 'namespace:pagename'.

===NAMESPACE and namespace===
The magic word <code><nowiki>{{NAMESPACE}}</nowiki></code> usually renders the [[WP:Namespace|''namespace'']] of a page if inserted in the wikitext of a page. The only time this doesn't happen is in Main namespace, where <code><nowiki>{{NAMESPACE}}</nowiki></code> will render a blank instead.

===Subpages===
[[WP:Subpages|Subpages]] (except for article pages) are also rendered by these magic words. For example, for the page named [[RetroWikipedia:Userboxes/Media/Film]], fullpagename would be <code>RetroWikipedia:Userboxes/Media/Film</code>, pagename would be <code>Userboxes/Media/Film</code>, and namespace would be <code>RetroWikipedia</code>.

===Some examples===
As an example, for the article [[Notability]]: the page name, <code><nowiki>{{FULLPAGENAME}}</nowiki></code> and <code><nowiki>{{PAGENAME}}</nowiki></code> would be <code>Notability</code>; and <code><nowiki>{{NAMESPACE}}</nowiki></code> would be blank. And for the page [[RetroWikipedia:Notability]]: the page name and <code><nowiki>{{FULLPAGENAME}}</nowiki></code> would be <code>RetroWikipedia:Notability</code>; <code><nowiki>{{NAMESPACE}}</nowiki></code> would be <code>RetroWikipedia</code>; and <code><nowiki>{{PAGENAME}}</nowiki></code> would be <code>Notability</code>.

===Related magic words===
Adding an E to the end of these variables, like {{tld|FULLPAGENAMEE}}, renders these variables encoded for use in [[MediaWiki]] [[URL]]s, i.e. with underscores replacing any spaces. Additional magic words for related variables include {{tld|ARTICLEPAGENAME}}, {{tld|ARTICLESPACE}}, {{tld|BASEPAGENAME}}, {{tld|SUBJECTPAGENAME}}, {{tld|SUBJECTSPACE}}, {{tld|SUBPAGENAME}}, {{tld|TALKPAGENAME}}, {{tld|TALKSPACE}}. See [[Help:Magic words#Variables|Help:Magic words]] for more details.

=={{anchor|Invalid page names}}Technical restrictions and limitations==
{{Main|RetroWikipedia:Naming conventions (technical restrictions)}}
[[RetroWikipedia:Article titles]] describes the policy for the correct naming of an article, but there are also technical restrictions to the naming of articles on RetroWikipedia, most of which are listed at [[RetroWikipedia:Naming conventions (technical restrictions)]]. The section [[WP:Page name#Changing the displayed title|Changing the displayed title]] explains how some technical restrictions may be overcome.

''Forward slash'' (/) in page names provides special functionality in a namespace where the [[WP:Subpages|subpage feature]] has been enabled. This feature is not active in RetroWikipedia's Main namespace, so a forward slash in an article name has no particular effect; but it may affect the behaviour of the corresponding talk page, as subpages are enabled in the Main Talk namespace. An example is the article [[GNU/Linux naming controversy]]; it doesn't have a subpage, but the talk page [[Talk:GNU/Linux naming controversy]] is a subpage of [[Talk:GNU]]. But this doesn't particularly cause problems.

:''For information on how to treat pages whose titles are affected by these limitations, see [[RetroWikipedia:Naming conventions (technical restrictions)]].''
In general, a page name can be any string of one or more Unicode characters. However, some strings of Unicode characters cause technical problems with the way RetroWikipedia functions, and so are limited or restricted.<ref>Page name naming is different on other projects.</ref> Note that these rules mostly apply to namespace as well as pagename. These limitations and restrictions include:
*A page name cannot begin with a lowercase letter in any alphabet, except for the German letter [[ß]].<ref>This is not true in all projects; for example, Wiktionary allows initial lower-case letters. This setting is configured using [[mw:Manual:$wgCapitalLinks|$wgCapitalLinks]]. A title can be ''displayed'' with an initial lower-case letter, when needed, by using DISPLAYTITLE, or the {{tl|lowercase title}} template.</ref>
*A page name cannot contain any of the following characters: <code>[[number sign|#]] [[less-than sign|<]] [[greater-than sign|>]] [[square brackets|&#91;]] [[square brackets|&#93;]] [[vertical bar||]] [[curly brackets|{]] [[curly brackets|}]] [[underscore|_]]</code> (which all have special meanings in wiki syntax); the Unicode [[Specials (Unicode block)|replacement character]] U+FFFD <code>�</code>; or any [[HTML character codes]], such as <code>&amp;amp;</code>.<ref>The plus sign + ''is'' allowed in page titles, although in the default setup for MediaWiki it is not. This is configured by setting the value of ''$wgLegalTitleChars'' in LocalSettings.php.</ref> A pagename also cannot contain 3 or more continuous [[tilde]]s <code><nowiki>~~~</nowiki></code>, as these are used for [[WP:Signatures|marking signatures on RetroWikipedia]].
*A pagename cannot begin with a [[colon (punctuation)|colon]] <code>:</code>.
*A pagename cannot be <code>.</code> or <code>..</code>; or begin with <code>./</code> or <code>../</code>; or contain <code>/./</code> or <code>/../</code>; or end with <code>/.</code> or <code>/..</code>.
*A pagename cannot exceed 255 [[byte]]s in length. Be aware that non-ASCII characters may take up to four bytes in [[UTF-8]] encoding, so the total number of ''characters'' that can fit into a title may be less than 255.
*A pagename cannot begin with any kind of namespace prefix, except a [[WP:Namespace#Pseudo-namespaces|pseudo-namespace]] prefix, by definition.
Namespace prefixes include: all [[WP:Namespace|subject and talk namespace]] prefixes (e.g., <code>RetroWikipedia:</code> and <code>User:</code>), [[WP:Virtual namespace|virtual namespace]] prefixes (<code>Special:</code> and <code>Media:</code>), [[Help:Namespace#Aliases|namespace aliases]] (e.g., <code>WT:</code>), [[Help:Interwiki linking|Interwiki linking]] prefixes (e.g. <code>Wikt:</code> for [[Wiktionary]]; <code>Q:</code> for [[Wikiquote]]), [[Help:Interlanguage links|Interlanguage link]] prefixes (e.g. <code>fr:</code>, <code>en:</code>). For example, an article about the album ''Q: Are We Not Men? A: We Are Devo!'' has the pagename ''[[Q. Are We Not Men? A: We Are Devo!]]'' because of the <code>Q:</code>.

Article titles beginning with a namespace prefix (e.g. {{nowrap|''RetroWikipedia: The big adventure''}}) are ''technically'' possible. However, the article would be in the wrong namespace, which would interfere with search and other functionality, and that space after the colon would have to be added with DISPLAYTITLE as described below. In such situations, the [[WP:Naming conventions (technical restrictions)#Colons|naming conventions]] recommend redirecting to an alternative title within mainspace. For example, the article ''Project: Mersh'' is named [[Project Mersh]], as ''Project:'' is a [[WP:Namespace#Aliases|namespace alias]] for the ''RetroWikipedia:'' namespace.
*A pagename cannot consist of only a namespace prefix.
*A pagename cannot begin or end with a space (which would be translated to an underscore in the URL).
*A pagename cannot contain % followed by 2 [[hexadecimal digit]]s (a pagename ''can'' have the character <code>%</code>, but it must be [[percent-encoding|percent-encoded]] as <code>%25</code> in the URL, to prevent it from being interpreted as a single character. To prevent ambiguity, pagenames cannot contain % followed by 2 hexadecimal digits).
*With namespaces, no capitalization of a namespace name, apart from the first letter, is allowed. Also, no spaces (which are translated to underscores) are allowed before or after the colon of a namespace name. For example, the following are not allowed: <code>HELP:</code>, <code>HeLp:</code>, <code>Help_:</code> or <code>Help:_</code> (with spaces rather than underscores).

==Changing the displayed title==
{{Shortcut|WP:DISPLAYTITLE}}
{{For|more information|Template:DISPLAYTITLE|RetroWikipedia:Naming conventions (technical restrictions)}}
{{About|changing the displayed title at the top of a page|actually changing the page title|RetroWikipedia:Moving a page}}
Although it is not possible to change a page title via the [[Help:Magic word|magic word]] <kbd>{<nowiki/>{DISPLAYTITLE:}}</kbd>, it is possible to stylize the way a page title is displayed at the top of its page to the reader. This should be done only if the article meets the criteria for a non-standard title format, as detailed in the [[WP:Article titles|RetroWikipedia:Article titles]] policy. Unlike on [https://github.com/wikimedia/operations-mediawiki-config/blob/ff3d2179963176d644170bb11df4ac38dbf74e8d/wmf-config/InitialiseSettings.php#L14763-L14785 a few other wikis], [[:mw:Manual:$wgRestrictDisplayTitle|$wgRestrictDisplayTitle]] is true on English RetroWikipedia, so only limited modifications can be made: the displayed title must still '''[[WP:Canonical|resolve]] to the true name of the page'''; i.e. if the displayed title is copied and pasted into a wikilink, the link should point to the original page.

To be more specific on when it can be used: DISPLAYTITLE allows changing the initial letter to lower case; changing the case of any letter in the namespace; adding one initial colon; changing spaces to underscores; adding a space after a namespace prefix; adding w: or en: at the start of a title; and adding formatting such as italics, bolding, superscripts, subscripts, etc. Some [[WP:Naming conventions (technical restrictions)#Forbidden characters|forbidden characters]] are not supported by DISPLAYTITLE (&lt; and &gt; are allowed in markup, and { and } are allowed for template transclusions). Since 2013 it is not possible to hide part of the title with <code><nowiki><span style="display:none;">...</span></nowiki></code>.

The syntax to use DISPLAYTITLE is <code><nowiki>{{DISPLAYTITLE:</nowiki><var>Desired title</var><nowiki>}}</nowiki></code>. However it is often applied through a [[Help:Template|template]], which includes {{tl|lowercase title}} (used on such articles as [[eBay]] and [[iPod]], and on categories such as [[:Category:macOS]]), {{tl|lowercase}} (used on templates such as [[:Template:iPhone models]]), and {{tl|italic title}} (commonly used for scientific names). Some infoboxes (such as {{tl|Infobox film}}) include a built-in DISPLAYTITLE to automatically italicize the page title.

{{Anchor|DISPLAYTITLE conflicts}}<!--linked in [[MediaWiki:Duplicate-displaytitle]]-->If there is more than one instance of DISPLAYTITLE with allowed modifications, and they do not all specify the same title, only the last such instance is enacted, with an error message generated. For example:

<span class="error">{{Suppress categories|{{int:Duplicate-displaytitle|<nowiki><i>Desired</i> title</nowiki>|<nowiki><i>Desired title</i></nowiki>}}}}</span>

The preferred solution to this problem is to remove one of the instances of DISPLAYTITLE. While it is possible to suppress the error via the "noerror" parameter, i.e. <code><nowiki>{{DISPLAYTITLE:</nowiki><var>Desired title</var><nowiki>|noerror}}</nowiki></code>, it is preferable to tweak the template that automatically includes the conflicting DISPLAYTITLE via parameter(s) usually described in its documentation. Many infoboxes have the option <code>|italic title = no</code> or <code>|italic_title = no</code> to omit an automatic display title.

A DISPLAYTITLE is applied when previewing in the Source Editor. Please test it before saving. A DISPLAYTITLE with disallowed modifications produces a warning in [[RetroWikipedia:PREVIEW|preview]]. It will not prevent a previous DISPLAYTITLE with allowed modifications from working. When using the [[RetroWikipedia:VisualEditor|VisualEditor]], the DISPLAYTITLE is not applied in the preview, nor are warnings given.

Please use <kbd><nowiki>{{DISPLAYTITLE</nowiki>{{highlight round|bc=lightgreen|''':'''}}<nowiki></nowiki><var>Desired title</var><nowiki>}}</nowiki></kbd>, rather than <kbd><nowiki>{{DISPLAYTITLE</nowiki>{{highlight round|bc=lightsalmon|'''&#124;'''}}<nowiki></nowiki><var>Desired title</var><nowiki>}}</nowiki></kbd>. This invokes the [[m:magic word|magic word]] directly instead of using the template. ''See [[Template:DISPLAYTITLE#Instructions|Template:DISPLAYTITLE § Instructions]] and [[Help:Magic_words#Behavior_switches|Help:Magic words § Behavior switches]]''.

===Draft articles===

The normal usage of <code><nowiki>{{DISPLAYTITLE:Draft:</nowiki><var>Desired title</var><nowiki>}}</nowiki></code> will appear to work but it will stop working when the draft is accepted since the new page name will be '''Desired title''' instead of '''Draft:Desired title'''.

The preferred way is to use templates (see above).  If that is not practical, <code><nowiki>{{DISPLAYTITLE:{{NAMESPACE}}:</nowiki><var>Desired title</var><nowiki>}}</nowiki></code> works and will continue to work if the page is moved into the main encyclopedia.

==Alphabetical order==
Where page titles are placed in alphabetical order by the system (as at [[Special:AllPages]]), [[Unicode]]-based ordering is used rather than the truly alphabetical ordering that would be expected. For details, see [[Help:Alphabetical order]].

==Spaces, underscores, and character encoding==
In page names, a blank space is equivalent to an underscore. A blank space is displayed in the large font title at the top of the page, while the URLs show an underscore. Wikilinks can use either spaces or underscores (spaces are preferred in article space).

[[Percent-encoding|Percent-encoded]] character codes, such as <code>%41</code> (which codes <code>A</code>) and <code>%C3%80</code> (which codes <code>À</code> or [[%C3%80|A-grave]]), are treated in pagenames as equivalent to their corresponding characters. The codes are generally used for most non-alphanumeric and non-[[ASCII]] characters in URLs; although the characters themselves may sometimes work as well, depending on browser. The reason why <code>%C3%80</code> works is because the [[UTF-8]] for A-grave is <code>C380</code> [[Hexadecimal|hex]].

Codes are converted into corresponding characters in link labels: <code><nowiki>[[%41]]</nowiki></code> and <code><nowiki>[[%C3%80]]</nowiki></code> are rendered as [[%41]] and [[%C3%80]]. The URL of the latter page is https://en.wikipedia.org/wiki/%C3%80 or https://en.wikipedia.org/wiki/À. It can be disputed whether the "real" name of the page is <code>%C3%80</code> or <code>À</code>, but in any case there cannot be distinct pages with these names.

In some cases, such as in templates, it is necessary to convert a page name represented by a variable into a form suitable for use in URLs: with underscores for spaces and with % codes for special characters. This can be done using the magic words described below; for full details, see [[mw:Help:Magic words]].

*Certain magic words ending with an extra "E", such as PAGENAMEE, NAMESPACEE, etc., return URL-encoded page names. For example, for this page, <code><nowiki>{{FULLPAGENAMEE}}</nowiki></code> gives <code>{{FULLPAGENAMEE}}</code>.
*The ''localurl'' and ''fullurl'' functions can be used to generate relative and full URLs to a particular page. Fullurl can also be used for interwiki references; but may not work for links to pages on a project with a different [[mw:Manual:$wgScript|$wgScript]].

If pagename variables are used ''within'' the localurl or fullurl functions, then use standard variables like <code><nowiki>{{PAGENAME}}</nowiki></code> etc., in the first parameter, where they will be encoded anyway; but then use "EE" variables, like <code><nowiki>{{PAGENAMEE}}</nowiki></code> etc., in the second parameter, the query string, if present. For example:
*<code><nowiki>{{fullurl:Special:Allpages|namespace=12&from={{PAGENAMEE}}}}</nowiki></code> gives here:
<code>{{fullurl:Special:Allpages|namespace=12&from={{PAGENAMEE}}}}</code>
*<code><nowiki>{{fullurl:Special:Allpages/{{PAGENAME}}|namespace=12}}</nowiki></code> gives here:
<code>{{fullurl:Special:Allpages/{{PAGENAME}}|namespace=12}}</code>

It is wrong to use:
*<code><nowiki>{{fullurl:Special:Allpages|namespace=12&from={{PAGENAME}}}}</nowiki></code> gives here:
<code>{{fullurl:Special:Allpages|namespace=12&from={{PAGENAME}}}}</code>, which is the wrong link.
*<code><nowiki>{{fullurl:Special:Allpages/{{PAGENAMEE}}|namespace=12}}</nowiki></code> gives here:
<code>{{fullurl:Special:Allpages/{{PAGENAMEE}}|namespace=12}}</code> . It works here, as the underscore, converted from a space, is not affected by the second conversion; but it does not work with special characters.

==See also==
*[[Help:Page name]]
*[[Module:Page]]

==Notes==
{{Reflist}}

{{RetroWikipedia help pages|collapsed}}
{{RetroWikipedia technical help|collapsed}}
[[Category:RetroWikipedia article title help|Page Name]]

[[ja:Help:ページ名]]