Serial Comma (Within List Of Similar Elements)
When creating a list or series of multiple things which are similar, commas should be used to separate each item in the list.
N.B. American English requires the use of a comma before the last and in a list; British English does not. Be sure to follow local protocol, particularly in formal writing.
Teenagers are often anxious to grow up, get a job, and move out of their parents’ house.
If you look carefully, there are three things teenagers want to do: 1) grow up, 2) get a job, and 3) move out of their parents’ house. These are similar things (they’re all things teenagers are anxious to do), so we need both commas.
I still have to buy a gift, pack the suitcases, and arrange for someone to water the plants while we’re at the wedding.
Mary needs bread, milk, and butter at the grocery store.
To use or not to use? The Oxford comma debate is a pretty heated one. Do you use Oxford (serial) commas?