Mary has requested that we do a post about the semicolon. I know that Lori is a little under the weather, and I'm sure I have more time on my hands than does Guido, so I'll do a quickie about this handy little punctuation mark.
I like the semicolon; I use it fairly often.
That's the first example of usage. Two independent clauses that are similar and are not joined by a conjunction such as and. The key is that the clauses must be able to stand on their own as a sentence. If and were in there, no further punctuation would be necessary. I like the semicolon and I use it fairly often.
I like the semicolon; however, I feel that I don't use it often enough.
I like the semicolon; I feel, however, that I don't use it often enough.
In this case, two independent clauses are joined by a linking adverb. The linking adverb is followed by a comma, or if within the second clause, offset by commas.
I like the semicolon, the exclamation point, and the ampersand; the semicolon is my favorite.
In this case, there are again two independent clauses, with internal punctuation in the first clause. This sentence could also include a linking adverb such as however in the second clause.
Some of my favorite punctuation marks are the semicolon, an underused mark; the colon, which introduces a list; and the exclamation point, which indicates emphasis or surprise.
This scenario shows the separation of a series in which each item uses internal punctuation. This is probably the usage I employ most often, for when some or all items in a series require a little further explanation, which is offset by commas.
In the first three scenarios, I think the important thing to remember is that the two clauses need to be able to stand on their own in order for the semicolon to be used correctly. A common error is for a writer to substitute a comma for the semicolon. This results in a comma splice, which is two independent clauses joined by a comma. I think many of us remember from school that a comma splice was a most egregious error!
I hope you'll give the semicolon another look; it separates elements of a sentence nicely, and can keep a writer from falling prey to run-on sentences.