Following is an ER diagram for an ATM. It illustrates the various entities involved in an ATM system. Here the entities are represented using square box shapes, the attributes using oval shapes, and the type of relationship using diamond-like shapes. Straight lines or links are used to connect different entities. The various entities involved inside the system include the ATM, the bank, the card, the customer, the technician, the transaction, the receipt generated after a transaction, and the account. The diagram can be used by various stakeholders to understand the workings of an ATM system.