Which protocol operates on port 80 and serves as the foundation of the World Wide Web?

The protocol that operates on port 80 and serves as the foundation of the World Wide Web is Hypertext Transfer Protocol (HTTP). HTTP is an application layer protocol designed for transmitting hypermedia documents, such as HTML, over the internet. It enables web browsers to retrieve web pages from web servers, facilitating the exchange of information that underpins the web browsing experience. When a user enters a web address in their browser, the browser uses HTTP to request the website files from the server, which then responds with the requested data, allowing the user to view the page.

Other protocols listed in the choices serve different purposes and operate on different ports. File Transfer Protocol (FTP) is used for transferring files between a client and a server, typically operating on ports 20 and 21. Secure Shell (SSH) is a protocol for secure remote login and other secure network services, commonly using port 22. Simple Mail Transfer Protocol (SMTP) is used for sending email messages and typically operates on port 25. Each of these protocols plays a specific role in data communication, but HTTP is uniquely positioned as the primary protocol for web traffic.