$_SERVER in PHP is very useful to getting lot of information about the PHP script in execution as well as the server/request details. $_SERVER is containing information such as headers, paths, and script locations. The entries(values) in this array are created by the web server.
1.$_SERVER[‘PHP_SELF’]
This php variable used to get currently executing script, relative to the document root. This variable returns currently executing script.
2. $_SERVER[‘REMOTE_ADDR’]
This php variable used to get remote ip address. That is, it used to get client ip address. It return client IP Address.
3. $_SERVER[‘SERVER_ADDR’]
This php variable used to get server ip address. we can get executing server ip address.
4. $_SERVER[‘REQUEST_URI’]
This variable use to make request server. The actual URI used in HTTP protocol (after GET or POST) to make the request.
5. $_SERVER[”HTTP_USER_AGENT’]
This variable used to get client browser details like to check which browser using client.
