Written texts lack the intonation of speech. Punctuation therefore helps to guide the reader through a text, clarifying the meaning by adding pauses of varying length and by indicating questions.

Punctuation in English should not be convoluted or mechanical, rather it should help the reader understand your meaning. Punctuation marks are like traffic signals: a full stop GB or period US means ‘stop’, and a comma means pause for breath or meaning. A semi­colon is a half stop – less than a full stop or period but more than a comma – and a colon signals something ahead. A question mark signifies of course a question, and a dash or parentheses mark additional information.

Using these punctuation marks, you should punctuate your text as if you were reading it aloud to an audience – for example if giving a presentation – to make your meaning clear.

Like spelling and grammar, punctuation is governed by rules, but these rules are in some cases arbitrary and inconsistent. And although your computer can offer basic punctuation advice, this should be treated with caution: with their mechanical application of rules and frequent lack of consideration of context, current grammar checkers can sometimes be a hindrance rather than a help.

The Writing Help sections below give advice on aspects of punctuation common in university and research writing. These include the comma, semicolon, colon, hyphenation, the possessive with ’s, and punctuating quotations.