php man page for _cookie

_COOKIE(3)								 1								_COOKIE(3)

$_COOKIE - HTTP Cookies

	An associative array of variables passed to the current script via HTTP Cookies.

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

       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 4.1.0	|						    |
       |	|						    |
       |	|  Introduced	  $_COOKIE     that	 deprecated |
       |	| $HTTP_COOKIE_VARS.				    |
       |	|						    |
       +--------+---------------------------------------------------+
       Example #1

	      $_COOKIE example

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

	       Assuming the "name" cookie has been set earlier

	      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.

       setcookie(3), Handling external variables, The filter extension.

PHP Documentation Group 														_COOKIE(3)