The Colon

The colon (:) seems to bewilder many peoplethough it's really rather easy to use correctlysince it has only one major use. But first please note the following: the colon is never preceded by a white space; it is always followed by a single white space in normal useand it is nevernever never followed by a hyphen or a dash — in spite of what you might have been taught in school. One of the commonest of all punctuation mistakes is following a colon with a completely pointless hyphen.

The colon is used to indicate that what follows it is an explanation or elaboration of what precedes it. That ishaving introduced some topic in more general termsyou can use a colon and go on to explain that same topic in more specific terms. Schematically:

More general: more specific

A colon is nearly always preceded by a complete sentence; what follows the colon may or may not be a complete sentenceand it may be a mere list or even a single word. A colon is not normally followed by a capital letter in British usagethough American usage often prefers to use a capital. Here are some examples:

Africa is facing a terrifying problem: perpetual drought.

[Explains what the problem is.]

The situation is clear: if you have unprotected sex with a strangeryou risk AIDS.

[Explains what the clear situation is.]

She was sure of one thing: she was not going to be a housewife.

[Identifies the one thing she was sure of.]

Mae West had one golden rule for handling men: "Tell the pretty ones they're smart and tell the smart ones they're pretty."

[Explicates the golden rule.]

Several friends have provided me with inspiration: TimIan andabove allLarry.

[Identifies the friends in question.]

We found the place easily: your directions were perfect.

[Explains why we found it easily.]

I propose the creation of a new post: School Executive Officer.

[Identifies the post in question.]

Very occasionallythe colon construction is turned roundwith the specifics coming first and the general summary afterward:

SaussureSapirBloomfieldChomsky: all these have revolutionized linguistics in one way or another.

Like all inverted constructionsthis one should be used sparingly.

While you're studying these examplesnotice again that the colon is never preceded by a white space and never followed by anything except a single white space.

You should not use a colonor any other markat the end of a heading which introduces a new section of a document: look at the chapter headings and section headings in the present document. It ishoweverusual to use a colon after a word, phrase or sentence in the middle of a text which introduces some following material which is set off in the middle of the page. There are three consecutive examples of this just abovein the secondthird and fourth paragraphs of this section.

The colon has a few minor uses. Firstwhen you cite the name of a book which has both a title and a subtitleyou should separate the two with a colon:

I recommend Chinnery's book Oak Furniture: the British Tradition.

You should do this even though no colon may appear on the cover or the title page of the book itself.

Secondthe colon is used in citing passages from the Bible:

The story of Menahem is found in II Kings 15:14–22.

Observe thatexceptionallythe colon is not followed by a white space in Biblical references.

Thirdthe colon may be used in writing ratios:

Among students of Frenchwomen outnumber men by more than 4:1.

In formal writinghoweverit is usually preferable to write out ratios in words:

Among students of Frenchwomen outnumber men by more than four to one.

Fourthin American usagea colon is used to separate the hours from the minutes in giving a time of day: 2:1011:30 (A). British Eng lish uses a full stop for this purpose: 2.1011.30.

Finallythe colon is used in formal letters and in citing references to published work.

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