php man page for globals

GLOBALS(3)								 1								GLOBALS(3)

$GLOBALS - References all variables available in global scope

	An  associative  array	containing references to all variables which are currently defined in the global scope of the script. The variable
       names are the keys of the array.

       Example #1

	      $GLOBALS example

	      <?php
	      function test() {
		  $foo = "local variable";

		  echo '$foo in global scope: ' . $GLOBALS["foo"] . "
";
		  echo '$foo in current scope: ' . $foo . "
";
	      }

	      $foo = "Example content";
	      test();
	      ?>

	      The above example will output something similar to:

	      $foo in global scope: Example content
	      $foo in current scope: local variable

       Note

	      This is a 'superglobal', or automatic global, variable. This simply means that it is available in all scopes  throughout	a  script.
	      There is no need to do global $variable; to access it within functions or methods.

       Note

	      Variable availability

	       Unlike all of the other superglobals, $GLOBALS has essentially always been available in PHP.

PHP Documentation Group 														GLOBALS(3)