Chosing a name for a page title is not a trivial task, because a title can designate only one page. If you make a bad choice and if you wish to change it later, that is possible, and Mediawiki will automatically redirect queries from the old to the new title. But you will be able to use it again only if you modify all the links previously created towards the old use of the title.
Criteria of choice are:
- A good title must be short, clear and non-ambiguous.
- It should contain words that the user is the most susceptible to query (above all the first word); an indication is given by headwords in usual dictionaries and encyclopedias.
- It should be distinctive enough to be recognised easily in a category, where it will appear by default in alphabetic order. For example, we preferred "Céleri cultivé (Candolle, 1882)" to "(Candolle, 1882): Céleri cultivé" because the last option would have classified all the 199 pages within letter C. Moreover, in the French version, you only have to type the first letters of the word "céleri" in the box "Search" to find the relevant articles (but not Apium graveolens which is the main page).
Mediawiki allows to use all the Unicode characters, apart those used in the software syntax. In the French Wikipédia, a decision in favour of the use of all the letters of the extended Latin alphabet has even been taken: decision. It is nevertheless anticipated that particular decisions can be taken for given languages. In Pl@ntUse, we recommend not to use accented capitals in titles.
In general terms, when a given use is usual in French or is standardised, this use is followed. So we write Tokyo, and not Tôkyô or Tōkyō, except of course within the article when reproducing the standardised graphical form of transcribed Japanese.
Arab words offer particular problems, as they have been subjected to various conflicting transcription standards and various ways to apply them (narrow or simplified). On the other part, publishers have often not had at their disposal the necessary fonts until recently, and publications present many variants. Unicode now allows to use scientific standards, which sould be done within an article (see Plant names in Arabic). But should we do it in the title?
As an example, if you copy the URL of the article title in English Abū Ḥanīfa Dīnawarī, you obtain http://en.wikipedia.org/wiki/Ab%C5%AB_%E1%B8%A4an%C4%ABfa_D%C4%ABnawar%C4%AB which is correct (click on it to be sure!) but incomprehensible. Indeed, with the URL http://en.wikipedia.org/wiki/Abū_Ḥanīfa_Dīnawarī, the page can also be found! But to find directly the title by typing, we should type characters in Unicode, what very few people will do, and what supposes that you have a recent computer. It is possible with Mediawiki to create "redirect" pages, but it seems more simple, once the standard graphical form of a name is established, to retain as title the same characters but without any diacritic sign, for example : Abu Hanifa Dinawari. This makes things easier for users, who can use their ordinary keyboard.
Wikipedia has elaborated a lot on this issue, which can be understood knowing that millions of pages do exist in major languages. You can consult the English and French versions. Even if we don't aggree with all the choices made, the arguments exposed are interesting.