php man page for _get

_GET(3) 								 1								   _GET(3)

$_GET - HTTP GET variables

	An associative array of variables passed to the current script via the URL parameters.

       $HTTP_GET_VARS contains the same initial information, but is not a superglobal. (Note that $HTTP_GET_VARS and $_GET are different variables
       and that PHP handles them as such)

       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 4.1.0	|						    |
       |	|						    |
       |	|  Introduced $_GET that deprecated $HTTP_GET_VARS. |
       |	|						    |
       +--------+---------------------------------------------------+
       Example #1

	      $_GET example

	      <?php
	      echo 'Hello ' . htmlspecialchars($_GET["name"]) . '!';
	      ?>

	       Assuming the user entered http://example.com/?name=Hannes

	      The above example will output something similar to:

	      Hello Hannes!

       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

	       The GET variables are passed through urldecode(3).

       Handling external variables, The filter extension.

PHP Documentation Group 														   _GET(3)