HTTP

HTTP, the Hypertext Transfer Protocol, is the protocol used to transfer data between a browser (or any client) and a web server over the internet. It was originally designed to transfer HTML documents, but today it carries most of the data a website serves — HTML, images, video, audio, scripts, and API responses alike. Its secure version, HTTPS, adds TLS/SSL encryption on top of the same underlying protocol so data can't be read or altered in transit.

How HTTP works

HTTP is a request-response protocol: a client sends a request — using a method such as GET (retrieve data), POST (submit data), or HEAD (retrieve headers only) — and the server replies with a status code and, usually, a body of content. The status code is what an automated check reads to decide whether a page "worked": codes in the 200 range mean success, 300s mean a redirect, 400s mean a client-side problem such as a missing page, and 500s mean the server itself failed to handle the request.

What an HTTP check verifies

An HTTP check does more than confirm a server answered — it can also verify the status code is the expected one, that the response arrived within an acceptable time, and that specific content appears (or does not appear) in the body, which catches cases where a server returns "200 OK" for a broken or error page. That last case is a common monitoring gap: the server is technically up and returning a normal status code, but the page itself displays an error, a maintenance notice, or a blank screen.

Common HTTP failure patterns

The most frequent HTTP-level problems are: a 5xx error from an overloaded or crashed application server, a 4xx error from a broken link or misconfigured route, a slow response caused by an unoptimized backend or database query, an expired SSL certificate breaking HTTPS connections entirely, and a redirect loop that never resolves to a final page. Checking HTTP from a single location can miss geography-specific problems — a CDN edge node failing in one region, for example — which is why checks from multiple locations catch more real-world failures than a single local request would.

How HostTracker checks HTTP

HostTracker runs HTTP/S checks from 300+ monitoring locations worldwide as one of 14 available check types, verifying status code, response time, and content in a single pass. Run a free check with the HTTP check tool, or set up continuous distributed monitoring to catch failures automatically as they happen. See the HTTP check guide for a full walkthrough of setting one up.