php man page for _post

_POST(3)								 1								  _POST(3)

$_POST - HTTP POST variables

	An  associative  array	of variables passed to the current script via the HTTP POST method when using application/x-www-form-urlencoded or
       multipart/form-data as the HTTP Content-Type in the request.

       $HTTP_POST_VARS contains the same initial information, but is not a superglobal. (Note that $HTTP_POST_VARS and $_POST are different  vari-
       ables and that PHP handles them as such)

       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 4.1.0	|						    |
       |	|						    |
       |	|  Introduced	   $_POST      that	 deprecated |
       |	| $HTTP_POST_VARS.				    |
       |	|						    |
       +--------+---------------------------------------------------+
       Example #1

	      $_POST example

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

	       Assuming the user POSTed 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.

       Handling external variables, The filter extension.

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