A network address is a unique identifier assigned to a device on a computer network. It allows devices to communicate with each other by specifying where data should be sent. The most common type of network address is an IP address, which can be either IPv4 or IPv6. Each device connected to the internet or a local network has its own network address, ensuring that data packets reach the correct destination. Network addresses are essential for routing data across the internet. When a device sends information, it includes the destination's network address in the data packet. Routers use this address to determine the best path for the data to travel, ensuring efficient communication between devices.