HTTP headers are the very first requests and responses sent between a web server and a browser. They contain all the key information needed to help the browser locate the correct server and ultimately the correct website or web page.
Included in HTTP headers are information about the client browser, the data on the requested web page, the type of server contacted, and other essential information to load the page. In some cases, HTTP headers will feature instructions directed at the browser to redirect to another page, or a noindex tag that tells search engines not to list the page on their search engine results pages.
Check your response headers with our Server Header Checker tool.