Does a comma go before the “and” in a series of three or more?
It’s confusing because different groups use punctuation differently. Journalists, for example, don’t use the comma because it takes up space.
We suggest you use the comma (called the “serial comma,” the “Harvard Comma,” or the “Oxford Comma”) to avoid confusion.
Consider these sentences without the comma:
I dedicate this book to my parents, Ayn Rand and Bertrand Russell.
Wait a minute. Your parents were Ayn Rand and Bertrand Russell?
We saw a man in a turban, a boy eating a sandwich and a parrot.
Whoa. Green feathers floating around the kid’s mouth. Bad visual.
The serial comma clears up the confusion:
I dedicate this book to my parents, Ayn Rand, and Bertrand Russell.
The book’s dedicated to four people: Mom and Pop, Ayn Rand, and Bertrand Russell.
We saw a man in a turban, a boy eating a sandwich, and a parrot.
The parrot is alive and well. No avicide.
It will never hurt you. It may help you. Use it.