What is a MAC address?

A MAC address, or Media Access Control address, is a unique identifier assigned to network interfaces for communications at the data link layer of a network. Each MAC address is typically assigned by the manufacturer of the network interface card (NIC) and is intended to uniquely identify each device on a network. This uniqueness helps ensure that data is sent to the correct device within a local network environment.

This identifier is composed of six pairs of hexadecimal digits and is essential in networking for processes such as local area network (LAN) communication. It helps facilitate proper data transfer between devices, ensuring that the data packets reach their designated destinations without interference or confusion.

The other options provided represent concepts related to networking but do not accurately describe what a MAC address is. For example, a temporary internet address refers to IP addresses, which may change over time, while system software for networking usually encompasses operating systems and drivers rather than MAC addresses specifically. A protocol for moving data across networks typically pertains to rules governing data transmission, such as TCP/IP, rather than identifying individual devices.