Student or Learner
Is it correct to say the difference between a debit card and credit card is this:
when you use a debit card, you use your own money so you make a purchase and the money is deducted from your account on the spot.
when you use a credit card, you use the bank's money so you make a purchase and you pay for it in the future.
Let's not forget to capitalize the first word in a sentence, please.
(I'd also put a comma before "so" in both sentences.)
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
FYI, in the United States, the lines between a debit card (sometimes called a check card) and a credit card are continually getting more blurry. For example, you can have a single card that acts as either a CC or a DB, depending on the merchant, or your choice at the time. Sometimes it’s automatically selected as DC if you enter a PIN (password), and CC if no PIN. (This can be of concern if you get cash-back: is that a cash advance, or just cash from your account?) Also, there are other concerns such as "overdraft protection". In some cases, if you debit your account with a DB for more than its available balance, you may be charged a fee (punishment) and/or you may be given credit. (Usually this line of credit is set up ahead of time.)