Network protocols govern the rules and conventions for data transmission over networks. They ensure efficient communication between devices by defining methods for error detection, data compression, and transmission speed. Common protocols include TCP/IP, which outlines how data packets are formed, transmitted, and received, ensuring reliable communication across the internet. By establishing standardized formats for addressing and routing, network protocols facilitate seamless data exchange and interoperability among devices. Overall, they are fundamental to maintaining a reliable and functional networking environment, supporting a wide range of applications.