This article details how to use semicolons and colons.
A semicolon creates separation. They often separate two main clauses that closely relate to each other but that could also be a standalone sentences. A semicolon creates more of a separation between thoughts than a comma; however, less than a period would.
One reason to use a semicolon instead of a period is to add variety to your sentence structure; for example, to avoid the use of too many short, choppy sentences. The two most important ideas need to closely relate to each other. Another reason to use a semicolon rather than a period is to highlight the relationship between the two ideas.
Semicolons are used to help clarify a list of items when some of those items already contain commas.
Semicolons are used to link (in a single sentence) two ideas together that are closely related to each other as an alternative to a full stop.
Use a semicolon between two independent clauses that connect by a conjunctive adverb (such as however, indeed, therefore) or transitional phrases.
Please note, semicolons are not used with coordinating conjunctions such as and, but, and or.
Colons follow independent clauses (clauses that could stand alone as sentences) and can be used to join ideas together, offer an explanation, or highlight something.
You can use colons to connect two sentences in instances when the second sentence summarizes, polishes, or clarifies the first sentence. Please note, both sentences must be complete and their subject matter should relate. You should never use them after a sentence fragment.
You can use colons before a list. You can also use them to introduce direct speech or quotations.
In summary, if properly used, semicolons and colons both have the ability to enhance the clarity of your writing.
Originally posted 5/14/2015 and happily updated 10/26/2017. Thanks for reading!