Apostrophes are one of the punctuation marks that many people seem to really struggle with. There are two main uses for apostrophes:

1. To indicate possession (eg
2. To indicate omission

One boy’s books - The books of one boy

Two boys’ books - The books of more than one boy

A woman’s rights - The rights of an individual woman

Women’s rights - The rights of (all) women

Common mistakes

Its or it’s?

This is the most common mistake people make about apostrophes – learn the rule, ‘it’s’ only needs an apostrophe if it means ‘it is’ not for the possessive.

Dates and some abbreviations

These represent plural nouns which are not possessors and so never need apostrophes.

Examples:

Source: The University of Hull (UK)