Everyone learns what a period means when they begin learning to write. It's finality, the end, and appears on the backside of a sentence. When you forget a period, your sentences bleed together like zebra running from a hungry lion. Can you imagine a story devoid of periods?
Did you know there's more than one use for a period?
As with every post on punctuation I'm going to be doing, this one uses information from The Chicago Manual of Style, 15th Edition.
Periods
While a period indicates you've come to the end of a declarative sentence, it can also be used to indicate something left out. Think about it. When you're abbreviating something, you put a period at the end. When you write, etc., there's a period on the end. Your period should always appear inside quotation marks (single or double), inside parentheses or brackets when they contain a complete sentence unless inside another complete sentence, and put three together to indicate a trailing off of speech (called an ellipsis).Colons can replace periods when introducing an inline list or when something is being described.
When not to use a period:
At the end of a heading, subheading, running head, signatures, or addresses (to name a few). If your subhead is in line with the text, a period is necessary to separate the subhead from the text. Never in a vertical list. These lists should be preceded by an opening statement and a colon. Line items don't get periods.
Abbreviations
When using a period in an abbreviation, it always goes directly after the last letter and all other punctuation rules apply as though the abbreviation is a complete word.
But did you know you can also put periods on the end of incomplete sentences and it be okay? If you're writing in colloquial style (a style more similar to spoken language), it's perfectly acceptable. It's also okay to use before block quotations unless the quote is introduced by a word that indicates "this is because" or tells you to look out for what's next. In those cases, a colon is appropriate.
Maybe you already knew all this; maybe you didn't. Either way, I do hope you pay close attention to the periods in your life and how they affect you.
Well, that's all for today, folks! Until next time, WRITE ON!
Jo