Predefined Variables

PHP provides predefined variables that represent external variables, built-in environment variables, and other information about the execution environment, such as the number and values of the arguments passed to the script in the CLI environment.

Table of Contents

Superglobals — Built-in variables that are always available in all scopes
$GLOBALS — References all variables available in global scope
$_SERVER — Server and execution environment information
$_GET — HTTP GET variables
$_POST — HTTP POST variables
$_FILES — HTTP File Upload variables
$_REQUEST — HTTP Request variables
$_SESSION — Session variables
$_ENV — Environment variables
$_COOKIE — HTTP Cookies
$php_errormsg — The previous error message
$http_response_header — HTTP response headers
$argc — The number of arguments passed to script
$argv — Array of arguments passed to script