What is a "network protocol"?

A network protocol is fundamentally defined as a set of rules that dictate how data is formatted, transmitted, and received across a network. It ensures that devices can communicate effectively and understand each other, regardless of their internal structures or the types of data being sent. These protocols specify various aspects such as data structure, error handling, and message sequencing, which are crucial for reliable communication between different systems.

For instance, common network protocols like HTTP (Hypertext Transfer Protocol) dictate how web browsers request and display web pages. Similarly, TCP (Transmission Control Protocol) ensures that data packets are sent and received in the correct order and without errors. This foundational aspect of protocols makes them essential for any functioning network, as they allow disparate systems to work together seamlessly.

The other options presented, while related to concepts in computer science, do not encapsulate the definition of a network protocol. Security measures pertain more to safeguarding data rather than the rules governing its transfer. Coding standards for AI programming and methods for tracking software changes are also unrelated to the concept of how data is transmitted and structured within a network.