Some people see grammar as a trifle, but I consider it important and the grammarian community would agree. However, would you believe there is dissension going on amongst grammarians about something very serious….a comma!
To be more precise, what has been dubbed the serial comma. There are those who think it is necessary, those who do not, and those who really don’t care.
A serial comma is the comma that comes in the last part of a list. A serial comma appears in the following example:
I need to buy milk, cheese, and potatoes at the grocery store.
A serial comma does not appear in this example:
I need to buy milk, cheese and potatoes.
AP style (the style most newspapers and magazines use) says that a serial comma is not necessary. Those who use other styles like MLA think that the comma needs to be there.
Personally I am a believer in the serial comma because it brings a sense of consistency to your list, your sentence, and your overall writing.
The decision is yours.