Explanation:
The trend is increasingly toward shorter and more straightforward sentences, which usually don’t require advanced punctuation. However, colons and semicolons can make your meaning clearer.

Both colons and semicolons can be used to unite two independent clauses — parts of a sentence that could stand as complete sentences on their own. “The bottom line for disaster recovery is the same for both large enterprises and SMBs” and “They need to stay in business” could each stand alone. Using a semicolon to unite the two clauses would indicate that those two ideas were more closely linked than if you made them separate sentences.

So why would you use a colon instead? Because a colon adds additional meaning about HOW those ideas are linked. It indicates that the first part of the sentence introduces the idea in the second or that the second part of the sentence explains the first.

The University of Victoria Writing Centre provides a simple introduction to colons and semicolons.

I’ve worked with writers who were very fond of semicolons for their arcane allure but didn’t know how to use them. The impression was that they’d randomly sprinkled semicolons throughout their text. If you don’t have a clear grasp of how to use advanced punctuation, you should avoid it. On the other hand, if you’d like to refine your writing, the rules are available. Learn and follow the rules and use colons and semicolons judiciously.

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