The file name of the script, which is related to document root.

$ _ SERVER ['php _ SELF '] # File Name of the script being executed, which is related to document root.
$ _ SERVER ['argv'] # parameters passed to the script.
$ _ SERVER ['argc '] # contains the number of command line parameters passed to the Program (if running in command line mode ).
$ _ SERVER ['Gateway _ interface'] # The CGI standard version used by the SERVER. For example, "CGI/1.1 ".
$ _ SERVER ['server _ name'] # NAME of the SERVER host where the script is currently running.
$ _ SERVER ['server _ soft'] # The string identified by the SERVER, which is provided in the header of the Response Request.
$ _ SERVER ['server _ Protocol'] # name and version of the communication PROTOCOL used to request the page. For example, "HTTP/1.0 ".
$ _ SERVER ['request _ method'] # request method for accessing the page. For example, "GET", "HEAD", "POST", and "PUT ".
$ _ SERVER ['query _ string'] # query string.
$ _ SERVER ['document _ root'] # ROOT directory of the DOCUMENT where the script is currently running. Defined in the server configuration file.
$ _ SERVER ['HTTP _ ACCEPT '] # Accept of the current request: Content in the header.
$ _ SERVER ['HTTP _ ACCEPT_CHARSET '] # Accept-Charset of the current request: Content in the header. Example: "iso-8859-1, *, UTF-8 ".
$ _ SERVER ['HTTP _ ACCEPT_ENCODING '] # Accept-Encoding of the current request: Content in the header. For example, "gzip ".
$ _ SERVER ['HTTP _ ACCEPT_LANGUAGE '] # Accept-Language of the current request: Content in the header. For example, "en ".
$ _ SERVER ['HTTP _ connection'] # CONNECTION of the current request: Content in the header. For example, "Keep-Alive ".
$ _ SERVER ['HTTP _ host'] # HOST of the current request: Content in the header.
$ _ SERVER ['HTTP _ referer'] # link to the URL of the previous page of the current page.
$ _ SERVER ['HTTP _ USER_AGENT '] # User_Agent of the current request: Content in the header.
$ _ SERVER ['https']-If accessed through HTTPS, it is set to a non-null value (on); otherwise, off is returned.
$ _ SERVER ['remote _ ADDR '] # the IP address of the user on the current page is being viewed.
$ _ SERVER ['remote _ host'] # The HOST Name of the user browsing the current page.
$ _ SERVER ['remote _ port'] # The PORT used by the user to connect to the SERVER.
$ _ SERVER ['script _ filename'] # the absolute path name of the currently executed SCRIPT.
$ _ SERVER ['server _ admin'] # administrator Information
$ _ SERVER ['server _ port'] # PORT used by the SERVER
$ _ SERVER ['server _ SIGNATURE '] # a string containing the SERVER version and virtual host name.
$ _ SERVER ['path _ TRANSLATED '] # basic PATH of the file system where the current script is located (not the root directory of the document.
$ _ SERVER ['script _ name'] # contains the path of the current SCRIPT. This is useful when the page needs to point to itself.
$ _ SERVER ['request _ URI '] # URI required to access this page. For example, "/index.html ".
$ _ SERVER ['php _ AUTH_USER '] # when PHP runs in the Apache module mode and uses the HTTP authentication function, this variable is the user name entered by the user.
$ _ SERVER ['php _ AUTH_PW '] # when PHP runs in the Apache module mode and is using the HTTP authentication function, this variable is the password entered by the user.
$ _ SERVER ['auth _ type'] # when PHP runs in the Apache module mode and is using the HTTP authentication function, this variable is the authentication TYPE.

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