Memefox interesting question.
From my experience each bank has it's own credit card options. However, banks are dependant on what country you are in and sometimes even where you are within that country. So the first question would be what country you are located in!
I'd suggest going to your local banks and asking about their credit card options for cash back. They want you to sign up so they'll go out of their way to explain how they work. You'll need to do your due diligence of checking in with each bank and comparing the cards. Make sure to read the details of each as that is where all the important information will be located.
Anyways let us know where you are located and maybe someone can offer some insight from there!