1. The SIX Basic Comma Rules
Thanks to a great book:
The LEAST You Should Know about English

2. Comma Rule #1 The Serial…Comma, not Killer…
Place a comma between items in a series as in the example below.
I have my laptop, my pens, my pencils, and my MP3 Player in my backpack.

3. Comma Rule #2
The Coordinating Conjunction Comma... Place a comma before a coordinating conjunction that joins two independent clauses. The coordinating conjunctions are: and, but, for, nor, or, so, and yet.
For Example: The best place to take a vacation is Chicago, but the best place to take a honeymoon is Hawaii.

4. Comma Rule #3 The Introductory Word or Phrase comma…
Always place a comma after an introductory word or phrase. See below.
John, what are you doing to my car? OR
As I walked down the street, I ran into a friend I hadn’t seen in years.

5. Comma Rule #4 The Interrupting Word/Phrase Comma…
Always place a comma before and after any word or phrase that can be removed from the sentence and still make sense.
For Example: John, the teacher, wrote his name on the board. OR
I ran down the street, though I didn’t have to, and fell down and hurt my crown.

6. Comma Rule #5 The Concluding Word/Phrase Comma…
Always place a comma before any word or phrase that is just tagged on at the end of the sentence. See below.
Is that you in the corner, John? OR
I hadn’t seen John in years, though that didn’t make much difference in our friendship.

7. Comma Rule #6 The Catch-all Comma…use it…
to separate numbers more than four digits long (1,000,000),
to separate city from state, (Paris, Texas),
to separate month & year (August 15, 1980),
before and after titles (James Smith, M.D., is no longer working here.),
or to prevent confusion (To err is human; to forgive, divine.)

8. Here’s the book…

9. Brought to you by
Tim McGinn
&
The NWACC
Writing Center