Superglobals

Built-in variables that are always available in all scopes

Description

Several predefined variables in PHP are "superglobals", which means they are available in all scopes throughout a script. There is no need to do global $variable; to access them within functions or methods.

These superglobal variables are:

  • $GLOBALS
  • $_SERVER
  • $_GET
  • $_POST
  • $_FILES
  • $_COOKIE
  • $_SESSION
  • $_REQUEST
  • $_ENV

Notes

Note: Variable availability

By default, all of the superglobals are available but there are directives that affect this availability. For further information, refer to the documentation for variables_order.

Note: Variable variables

Superglobals cannot be used as variable variables inside functions or class methods.