The Bank of Delaware invented the debit card in 1966. By the 1970s, other banks caught onto the idea and began making similar cards for their own customers.
Debit cards are issued from a bank or credit union, and linked to a personal checking account. The card essentially acts as a cash transaction but without the need for physical cash. Each user creates a unique personal identification number associated with the card that is entered into a keyboard at time of purchase; since the card is linked to a checking account, the money for the transaction will be deducted directly from the given account.