Do you use a comma before the word and?

Answer 1

You only use a comma when the words you are listing are not related.

Example: I needed a helmet, a safety vest, and food. Safety vest is not related to food so that's when you add a comma before the word and. But if it was: I needed an apple, banana and a pear- They are all related because they are all fruits= related.

Another answer:

If you are referring to lists of words, the use of the comma before the 'and' and the final item in the list is a matter of personal preference. It indicates where you would pause if you were speaking the sentence aloud, and has nothing to do with whether the items in the list are related. (If it did, how would you decide whether words were related? Apple, banana, and cheese - all food, but not all fruits?)

If you were speaking the two example sentences given by the previous contributor, you would be no more likely to pause between 'safety vest' and 'and food', than between 'banana' and 'and a pear'. Or to put it another way, you would be no less likely to pause between 'banana' and 'and a pear' than between 'safety vest' and 'and food'.

Commas, like other punctuation, are there to help us make ourselves clear. I always use that comma, which is known as the Oxford comma, because I would always pause before saying the 'and'. But that is a preference, not a rule.

Answer 2

The word and is a conjunction. As such a comma is typoically used when a conjunction joins words in a series of three or more, phrases, or clauses. The correct form would be:

"***, and..."

Always.

Answer 3

Not usually.