A network protocol is a set of rules and conventions that govern how data is transmitted and received over a network. These protocols ensure that devices, such as computers and routers, can communicate effectively, regardless of their underlying hardware or software. Common examples include the Transmission Control Protocol (TCP) and Internet Protocol (IP), which work together to facilitate reliable data transfer across the internet. Protocols can be categorized into different layers, such as the Application Layer, which deals with user interfaces and applications, and the Transport Layer, which manages data flow and error correction. By adhering to these protocols, devices can exchange information seamlessly, enabling services like web browsing, email, and file sharing.