A bank network refers to a system of interconnected banks that work together to provide financial services to customers. This network allows banks to share resources, information, and technology, making it easier for them to offer services like ATM access, online banking, and wire transfers across different locations. These networks can be local, national, or international, enabling customers to access their accounts and conduct transactions from various locations. By collaborating within a bank network, financial institutions can enhance their service offerings, improve efficiency, and ensure better security for their customers' financial activities.