Why are some plastic cards called debit cards?

With debit cards often it must  have a credit balance in your accounts with rare exceptions.

For Banks-

When we deposit money- They credit your account. Because they owe us the money

When we withdraw money- They debit your account. Because they returned back the money

So ATM withdrawal card is know as Debit Card.

Thanks for the invitation and sorry for late reply  I agree with all the answer given.

Because transactions are instantly debited from your bank account.

A debit card (also known as a bank card or check card) is a plastic payment card that provides the cardholder electronic access to his or her bank account.

Debit card is a instrument for payment acting against the promise to pay cash value. It is called debit card because the bank will see to that it will be payed only to the amount of money debited in to it. That being a plastic once you lose it and informed of the lose it becomes nothing but a value less piece of plastic.

Debit card is having the function to debit what ever is available in our account, it can use the existing amount only. Whereas credit card meant to have credit so whenever we are doing transaction through credit card we are borrowing money from bank as credit that why it is called credit card.

Card is accessible electronically to the ATM network used a check to pay d provide this card to computers or drag money machine

AGREE WITH ALL ANSWERS