Microsoft® Manual of Style, Fourth Edition

Nouns

Plural nouns

In general, form the plural of a noun by adding s. If the noun already ends in s, form the plural by adding es. This rule applies to proper nouns as well as common nouns.

Microsoft style

the Johnsons

the Joneses

Form the plural of an abbreviation by adding an s with no apostrophe.

Microsoft style

ISVs

DBMSs

If an abbreviation already represents a plural, do not add an s. For example, the abbreviation for Microsoft Foundation Classes is MFC, not MFCs.

Form the plural of a single letter by adding an apostrophe and an s. The letter itself (but not the apostrophe or the ending s) is italic.

Microsoft style

x’s

Form the plural of a number by adding an s with no apostrophe.

Microsoft style

486s

the 1950s

International considerations

Do not add (s) ...