You have to be a memeber of AMEX to get Optima. At least a few years back when I had it.
One of the reasons they changed the name from BankAmericard to Visa was that in Canada Bankamericard was Chargex and in other countries other things. It simplified things to call it VISA
Also Discover cards start with 6011.
DC’s start with 3. Basically Carte Blanche = DC.
And don’t you guys forget JCB. Japanese Credit Bureau. A lot of hotels take that one.