It is known to me that there are several types of commas, I recall the oxford comma is most important.
For those of you wondering what the Oxford Comma (OC) actually is, I have one question: what on earth are you doing reading an up-market website like this?
So for your delectation and delight here is a definition of the OC: it's the insertion of a comma after the penultimate item in a list, just before the and--for example, ?'coffee, cream, and sugar' instead of ?'coffee, cream and sugar'.
Slightly altered version of
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