Today, I'm going to show you my inner editor and rant about a peeve of mine, the absent serial comma.
I have long been a huge fan of the serial comma. In this modern age, when it has been decided that "literally" can mean "not literally", we seem to be getting away from the "old ways". There are those who believe that just because it's always been that way doesn't mean it's the best way, and then there are those who believe in change for the sake of change. In most recent publications I've read, the serial comma, also known as the Oxford comma, has been left out. Here's why I believe it's wrong.
A serial comma is used in what we call "items in a series". It is the last comma before the "and" and the last item in the series. The new way of thinking is that it is not always needed. As a person who has to interpret and edit manuals on technical subjects and systems that I am not always familiar with written by people who may not have been grammatical experts by any stretch of the imagination, it's not always clear exactly what the original author meant when they left out the comma. For example, if you were to say that "the departments in the company include administration, operations and learning and development", it's difficult for me to know if you mean three departments or four.
The argument in favor of omitting the series comma is contingent, at best. In this article, Lynn Gaertner-Johnston discusses a study she did of 11 current style guides. Nine of the 11 guides supported the use of the serial comma, and the other two said that it would be okay to omit if it didn't cause confusion. The reasoning is very subjective because most people aren't very skilled in grammar. If they were, they would be able to recognize the need for the serial comma. So, what happens? It gets left out across the board, which means that, most of the time, omitting the comma causes confusion.
The bottom line is simple logic: it is better to ALWAYS include the serial comma and be RIGHT all of the time than to ALWAYS omit it and be WRONG most of the time.