Most of us think we know when to use commas and when to leave them out. We went to elementary school, after all. Still, many of us get it wrong from time to time ... do you?
A comma splice happens when you place a comma (instead of a period or a semicolon) in between two complete sentences with no conjunction separating them.
An independent clause is one that contains a subject and a predicate -- it's a complete sentence that can stand on its own.
Commas typically indicate that what follows or fits between them is not essential to the meaning of the sentence.
Also called an "essential clause," a restrictive clause is one that is crucial to conveying the complete meaning of the sentence. It is not surrounded by commas.
The Oxford comma, sometimes called the Harvard comma or serial comma, is the comma that precedes the final item in a list.
In Europe and elsewhere, the date is written with the day first, then the month and then the year, with no commas.
The phrase "such as," which introduces examples, should never be followed by a comma. The same goes for "including."
The word "which" introduces a descriptive clause that is nonrestrictive (nonessential), and nonrestrictive phrases take a preceding comma.
A restrictive clause describes a preceding noun and has no commas, since it cannot be removed from the sentence without affecting the meaning (there may be other stores in the area, and we're talking specifically about the one that sells soap).
While preceding a name suffix with a comma (Sammy Davis, Jr.) used to be common practice, it has recently fallen out of favor. Now, there's no comma separating the name from the essential suffix.