Final answer:
A smart card is an electronic device the size of a credit card that provides secure network access, manages digital certificates, or stores value, and can perform authentication and application processing.
Step-by-step explanation:
The item about the size of a credit card that allows access to a network and its resources is referred to as a smart card. A smart card is a physical electronic authorization device, which contains an embedded integrated circuit chip that can be either a simple memory circuit or a microprocessor with memory. This embedded microchip can process data and often is capable of providing secure access to a network, managing digital certificates, or storing value (such as in the case of prepaid cards). Because of its processing power and storage capabilities, the smart card can perform personal identification, authentication, data storage, and application processing, making it a versatile security tool in organizations.