HTTP (HyperText Transfer Protocol) is the foundational protocol enabling communication between web browsers and servers. When you visit a website, your browser sends an HTTP request to the server, which responds with the requested web page content. HTTP defines how messages are formatted and transmitted, and how servers and browsers should respond to various commands. HTTP is stateless—each request is independent, though cookies and other mechanisms maintain session information across requests. Standard HTTP transfers data without encryption, making it vulnerable to interception. HTTPS (HTTP Secure) adds encryption for security. Modern web standards strongly encourage HTTPS for all sites, and browsers increasingly warn users about non-secure HTTP sites. Understanding HTTP basics helps comprehend how the web works, why HTTPS matters for security, and how website performance is affected by request/response patterns.