An ATM card (also known as a bank card, client card, key card or cash card) is a card issued by a bank, credit union or building society that can be used at an ATM for deposits, withdrawals, account information, and other types of transactions, often through interbank networks.
Some ATM cards can also be used:

  • at a branch, as identification for in-person transactions
  • at merchants, for EFTPOS (point of sale) purchases

ATM cards are typically about 86 × 54 mm, i.e. ISO/IEC 7810 ID-1 size.
Unlike a debit card, in-store purchases or refunds with an ATM card can generally be made in person only, as they require authentication through a personal identification number or PIN. In other words, ATM cards cannot be used at merchants that only accept credit cards.