Glossary

HTTP

Definition: HyperText Transfer Protocol — the foundational communication protocol used to transfer data on the web, without encryption.

HTTP (HyperText Transfer Protocol) is the protocol that defines how messages are formatted and transmitted on the World Wide Web. It is the foundation of data communication on the internet — but unlike HTTPS, it does not encrypt the data it carries.

How HTTP Works

HTTP follows a request–response model. A client (usually a browser) sends an HTTP request to a server, and the server responds with the requested resource (an HTML page, image, JSON data, etc.).

  • GET — Retrieve a resource.
  • POST — Submit data to a server (e.g. a form).
  • PUT / PATCH — Update an existing resource.
  • DELETE — Remove a resource.

HTTP vs HTTPS

HTTP transmits data as plain text, making it vulnerable to interception on public networks. HTTPS adds TLS encryption, which protects data in transit. Today, Google Chrome flags all HTTP pages as "Not secure".

HTTP Status Codes

Every HTTP response includes a status code indicating the outcome:

  • 2xx — Success (200 OK)
  • 3xx — Redirection (301 Moved Permanently, 302 Found)
  • 4xx — Client error (404 Not Found, 403 Forbidden)
  • 5xx — Server error (500 Internal Server Error)
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