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HTTP

HTTP (the Hypertext Transfer Protocol) is a set of rules that lets a client, such as a web browser, request information from a server and receive a response. The browser might request a page, an image, or other data. The server responds with a result, a status code, and sometimes the requested content.

What happens when a browser makes an HTTP request?

When you open a web address, the browser uses DNS to find an address for the site's host, connects to a server, and sends an HTTP request for a resource. A resource is the item being requested, such as the page at /about. The server processes the request and returns an HTTP response. A status code such as 200 indicates success, while 404 means the requested resource was not found.

For example, when Riley visits http://example.com/about, the browser asks for the /about resource at example.com. The server may return the page content with a success response. If the page has moved, the response may instead tell the browser to go to a different URL. HTTP describes the request and response; it does not itself store the website's files.

Is HTTP encrypted?

Plain http:// does not provide the connection protection used by HTTPS, known as TLS. Without that protection, data sent over the connection may be visible or altered by parties able to observe or interfere with the network path. HTTPS uses HTTP over a protected connection, typically provided by TLS or, for HTTP/3, by QUIC with TLS security.

HTTP is an application protocol: it describes what the browser and server say to each other. Other network systems carry the messages between them. A working HTTP response does not by itself show that the page is trustworthy or that its content is safe.

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