MOS:SPELL
This is the Manual of Style (spelling) guideline page, a handy reference for editors.
Please note: If you are not familiar with a spelling, please do some research before changing it – it may be your misunderstanding rather than a mistake, especially in the case of American and British English spelling differences.
This table gives the accepted spellings (following government guidelines and major dictionaries). It is by no means exhaustive, but rather an overview. When two variants appear, the one listed first is more widely used. (For example, in Australia, New Zealand, South Africa, the UK and Ireland, ageing is more common than aging; in Canada and the US, aging is more common.)
The spelling systems of unlisted Commonwealth countries, such as India, Pakistan and Singapore, are generally close to the British spelling system, with possibly a few local differences. Some non-Commonwealth English-speaking countries, such as the Philippines and Liberia, have spelling systems closer to American spelling.
Throughout this section, the variants here regarded as "British" are also used in Australia (in most cases), as well as in other Commonwealth countries and in Ireland. Canadian spelling combines British and American.
In both British English and American English, many words have variant spellings, but most of the time one variant is preferred over the other. In dictionaries, the preferred spelling is listed first among the headwords of an entry. Examples follow:
Older sources use many archaic variants (such as shew for show), which are not to be used outside quotations except in special circumstances (for example, quire may be used instead of choir in architectural contexts).
When archaic spelling is used in the title of a work, modernize the spelling in the text of the article but retain the original spelling in the references. For example, the text of an article might read "Thomas Ady attacked the Demonology of King James..." while the citation should read Daemonologie, In Forme of a Dialogie, Diuided into three Bookes. By James Rx, 1597....". Adding a <!-- comment --> may help prevent well-meaning editors from correcting the spelling "mistakes".
As per WP:Manual of Style § Quotations, archaic glyphs should be modernized, including within quotations and titles (e.g., æ→ae, œ→oe, ſ→s, and ye→the). Archaic spellings (including capitalization, punctuation, and emphasis that would be non-standard today) are retained in quotations, and we rarely need to provide any translations into Modern English if the source material is Elizabethan or later. For Middle English, treat it on a case-by-case basis, but always provide translation for Old English.
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