Why does an ATM need a modem or network connection?

An ATM needs a modem or network connection to communicate with the bank's central servers for transaction processing. This connection allows the ATM to verify account balances, authorize withdrawals, and update transaction records in real-time. Additionally, it enables the ATM to receive software updates and security patches, ensuring it operates smoothly and securely. Without this connection, the ATM would be unable to perform its primary functions effectively.