Editing Encyclopedia:Manual of Style (section)

===Years and longer periods===
{{Main|MOS:DECADE|MOS:CENTURY|MOS:ERA}}
*Do not use ''the year'' before the digits ({{xt|1995}}, not {{!xt|the year 1995}}), unless the meaning would otherwise be unclear.
*Decades are written in the format {{xt|the 1980s}}, with no apostrophe. Use the two-digit form ('80s) only with an established social or cultural meaning. Avoid forms such as {{!xt|the 1700s}} that could refer to ten or a hundred years.
*Years are denoted by [[Anno Domini|AD and BC]] or, equivalently, [[Common Era|CE and BCE]]. Use only one system within an article, and do not change from one system to the other without good reason. The abbreviations are written without periods, and with a [[#Non-breaking spaces|non-breaking space]], as in {{xt|5&nbsp;BC}}. Omit AD or CE unless omitting it would cause ambiguity.

More information on all the above topics can be found at {{section link|Wikipedia:Manual of Style/Dates and numbers|Chronological items}}, including the handling of dates expressed in different calendars, and times corresponding to different time zones.