Does a comma go before the word because?

It depends on the context. Here are the general rules:

When to use a comma before "because":

* When "because" introduces a dependent clause that follows an independent clause.

* Example: "I went to the store, because I needed milk."

When not to use a comma before "because":

* When "because" introduces a phrase that is not a dependent clause.

* Example: "I went to the store because I needed milk."

In short, use a comma before "because" when it introduces a clause that can't stand alone as a sentence. If it's just a phrase explaining the reason, no comma is needed.