Superglobals

SuperglobalsBuilt-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:

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.