HTTP (HyperText Transfer Protocol) is the protocol responsible for delivering web pages over the Internet. It is a request-response, Application-Layer (Layer 7) protocol that defines how clients (web browsers) and web servers exchange resources.

How a page is delivered:

• The browser issues an HTTP request — most commonly a GET to retrieve a resource, or a POST to submit data — identifying the resource by its URL.
• The server responds with a status code (for example 200 OK or 404 Not Found) plus headers and the requested content (HTML, images, scripts).
• HTTP is stateless by design; session continuity is layered on top using cookies and tokens.
• It typically runs over TCP on port 80; its encrypted variant HTTPS uses TLS on port 443.

The other protocols serve entirely different application functions. SMTP (Simple Mail Transfer Protocol) sends email between mail servers. FTP (File Transfer Protocol) is dedicated to transferring files between hosts, not rendering web pages. ARP (Address Resolution Protocol) works at a much lower level, mapping IP addresses to MAC addresses within a local network, and never carries web content. Only HTTP is purpose-built to fetch and deliver web pages.