Colon vs Semicolon: When to Use Which

Colons and semicolons are punctuation marks that serve distinct purposes in writing. The use of a variety of characters is necessary when writing with the Roman alphabet because it enables a reader to see what words are associated with what other words, in a way that is usually clear from a person’s tone of voice when a language is spoken, but can give rise to confusion if there are no marks to break up a running written text.

Consider the following unpunctuated text:

Why did you choose this path as she pondered looking at her intently he replied sometimes its the unexpected twists they add excitement the possibilities were endless however she hesitated life he continued is a series of choices each one shapes our journey.

In spite of the advances of technology, punctuation is still problematic for word-processors. While they can make suggestions, it is impossible for word-processors to know your meaning, because you as the writer show the very nuances of your meaning by what punctuation you choose and the precision with which you place it.

This is true of speech marks, question marks, exclamation marks, hyphens, dashes, colons and semicolons. They add clarity to a text, but many writers struggle to know when to use a colon or a semicolon rather than, for instance, a comma.

For more on comma use, please see the relevant article.

To know when to use a colon or semicolon, read on.

The colon :

Within the body of written text, the primary use of the colon, that looks like two dots above each other, is to introduce lists, examples or explanations:

• There are three things I love: chocolate, films and walking.

Colons also help to introduce quotations:

• Shakespeare said it best: “All the world’s a stage.”

Notice in this post how the sentence introducing each example utilises a colon for that purpose.

A colon also has several other uses, such as in marking the time in numerals between the hours and minutes:

• The meeting is scheduled for 3:30pm.

However, a simple point can also be used for this purpose; it is a stylistic choice.

A colon is also used to express a ratio of numbers. For example, if there is one human for every 1.4 billion insects in the world, one would write the ratio as 1 : 1,400,000,000.

There are also approximately five pet dogs for every four pet cats in the world, so as a ratio this would be expressed as 5 : 4.

When not to use a colon

The colon is often misused and confused because people forget that its very purpose in writing (outside of its use in representing numerical figures) is to introduce something.

Therefore, when words have already been used to introduce what follows, a colon is redundant.

After introductory phrases such as “for example” or “such as” it is not necessary to use a colon. These phrases already serve to introduce examples. Instead, a comma can be used or the examples may flow naturally within the sentence without any need for additional punctuation:

• There are many fruits at the grocer’s shop. For example, apples, bananas and oranges.
• There are many fruits at the grocer’s shop, such as apples, bananas and oranges.

Colons are sometimes erroneously substituted in place of other punctuation. There is a great variety of punctuation characters and each has been devised to serve an individual purpose. A colon should never be overused. Colons are effective when used to introduce explanations, definitions or lists, but they should be used judiciously and in accordance with specific grammatical rules and conventions. If in doubt, consider alternative punctuation or restructuring a sentence for clarity.

The semicolon ;

The semicolon looks like a comma with a dot above it. It is used to join independent clauses, to link independent clauses with transitional expressions, to separate items in a list with internal commas, or to clarify items in a complex list.

A semicolon is used to join two closely related independent clauses (complete thoughts):

• I love to write; I find it therapeutic.

Both of the above independent clauses could also be expressed as short and complete sentences in their own right. However, because the thought expressed in both is related, they work well expressed together in one sentence, and the semicolon serves to show that although they are separate independent clauses they belong together and are related to one and the same idea.

For more on what a clause is in grammar, please visit the relevant article.

A semicolon is used before a transitional expression to link independent clauses. A transitional expression such as ‘however’ or ‘therefore’ often indicates that the second independent clause is strongly associated with the aforementioned clause:

• The weather was ideal for a picnic; however, we decided to stay indoors.

Semicolons also serve to clarify complex lists. When items in a list contain internal commas, semicolons are used to separate the list items to avoid overpopulating, and thus confusing, a sentence with commas:

• The conference attendees came from London, England; Paris, France; and Rome, Italy.

• The team included Sam, the project manager; Emily, the designer; and Alex, the developer.

Capitalisation after colons and semicolons

In UK English, the first word after a colon should not normally be capitalised (unless the word is a proper noun), even if the words that follow it form a complete sentence:

• The world is faced with a difficult issue: climate change.
• The world is faced with a difficult issue: should it tackle climate change or leave it to future generations to worry about?
• The world is faced with a difficult issue: it needs to make decisions on climate change before it is too late.

However, if the colon is followed by quoted text, there may be an exception:

• Shakespeare said it best: “All the world’s a stage.”

The other exception in UK usage is as used throughout this post, when a colon introduces a list of examples following on subsequent lines, as with the colons introducing all the bullet-pointed lists in this article.

On the contrary, American English does capitalise the first word after a colon if it begins a complete sentence.

After a semicolon, in both UK and US English, the following word is not capitalised unless it is a proper noun:

• We visited three cities; Paris was our favourite.

Conclusion

In conclusion, the proper use of colons and semicolons in writing is crucial for clarity. While colons introduce lists, examples and explanations, semicolons connect closely related independent clauses or clarify complex lists.

It is essential for writers to understand the distinct purposes of these punctuation marks and employ them with care. Overuse or misuse of any one character of punctuation can lead to confusion.

If you have any questions or comments, please do enter them below.

BIBLIOGRAPHY

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https://dictionary.cambridge.org/dictionary/english/