Jennifer’s question: “As I read through cover letters and resumes I’m noticing an overwhelming number of people are putting a comma before ‘and,’ e.g., calculate prices, enter data, and create invoices. Why is this happening? It’s sure not the way we were taught to write when I was in school!”
BizWritingTip response: This is a style issue rather than a grammar one. This means using — or not using — the comma before “and” is not considered an error.
Like our reader, when I went to school, we were taught not to put a comma before the final “and” in a series. I have never figured out why.
Today, the guideline is to insert a comma before the final “and” if it assists with clarity. This is often subjective as the writer must determine how clear the information is.
They will visit London, Paris and Athens. (There is no need for a comma as these are three known cities.)
The American flag is red, white and blue. (This is common knowledge.)
Breakfast consisted of cereal, bacon and eggs, bread and butter, and coffee. (The comma before the “and” tends to chunk the information more clearly.)
Frankly, I like the comma before “and.” Business people tend to skim documents today. The comma creates sound bites and allows for emphasis.
You should hire my friend. She is knowledgeable, conscientious and enthusiastic. (This is easy to understand. Therefore, there is no need for a comma.)
You should hire my friend. She is knowledgeable, conscientious, and enthusiastic. (This is also correct and is my preference because the comma before “and” emphasizes three separate but equally important characteristics.)