I only carry one credit card -- leave the other one million cards on my bedroom dresser. I carry it to buy gas and other things I see while shopping. Then I always pay the entire balance when I get the bill so that I don't have to pay intgerest.
I always take the debit card instead because it only lets me spend as much as I have in my account so its less of a risk if it gets stolen. Only time the credit card gets used is if it will be something expensive (if you pay for expensive stuff usng a cc and it does not come or is bad, you get certain protections under UK law) or if I dont know how much something will be / know I cant afford it. Always gets paid off real quick though.
Yeah, the credit card, a necessary evil, always use it, but also always pay it up in time. I have plenty of foolish friends who spend half their income on cedit card interest. Some of those cards make a loan shark look friendly! Also remember that Joe Biden was behind much of the legislation making this possible.