Wikipedia:Naming conventions (technical restrictions)

Restrictions on page titles are listed at . The most commonly encountered problems are that:

There are two basic ways of handling a situation where the desired title of a page is technically impossible:

These templates should never be substituted (subst). To see which articles have these naming problems you can click on "What links here" in the toolbox for each template. If the template is substituted, it will no longer be linked.

Examples of articles affected by this problem are:

This also means that the page Long s, on the character ſ, cannot be moved to (or redirected from) ſ, as ſ is a lowercase letter whose uppercase form is S.

To fix this problem, place the {{}} tag at the top of the article page (and optionally at the top of its discussion page). This will cause the article title to be displayed with the initial letter in lowercase, as at eBay. Note that it does not fix every occurrence, like the history, edit, log pages, or the browser address bar (it only affects the page title on the rendered HTML page and tab/window title bars).

Due to clashes with and HTML syntax, the following characters are not allowed to be part of page titles (nor are they supported by DISPLAYTITLE):

For articles about these characters, see number sign, less-than sign, greater-than sign, bracket (covers several characters), vertical bar.

If the desired title of an article contains any of these characters, then an alternative title must be used instead. Often, you can simply remove the characters (e.g. MARRS instead of M|A|R|R|S). However, it may be necessary to spell out the character (e.g. C-sharp instead of C#) or use another substitute. Note that the sharp sign ♯ (different from the keyboard # character) can be used, as in C♯ (musical note).

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