The server headers check tool commonly referred to as a server header checker is used to return a number of important results. None of these results are more important than the other really, it just depends on the information you are seeking. After entering a URL you'll see the server headers check utility results displayed include CharacterSet, Content-Type, Last-Modified, Server, StatusCode, Set-Cookie, and X-Powered-By.
Each of the returned results is pretty self explanatory and will definitely help you in your information gathering. Each visitor might have a different reason for determining the server headers of a particular URL. They might want to know what kind of server the site is hosted on or if the page is being served up via a cached file. If you have your own website, this tool will help you determine if your status code is returning the correct response.