If, for some reason you need to declare
a dynamic variable global, say $usertype1, $usertype2 etc... 
do it like this:
                $i=1;
                $ready=#number of 
                        generated 
                        variables#
 		while ($i < $ready) {

		$var="usertype$i";
		global $$var;
		
                ###do the action with 
                   the var, for 
                   example:##
                echo $$var; 
		$i++;
		}

I had trouble digging this out, and searches for various terms (memory
model, garbage collection, &c) were not productive. 

PHP4 uses reference counting for garbage collection. Details about this
system can be found here:

a great way to pass variables from page to page... 
select: How PHP/FI handles GET and POST method data
ie:
   
/cgi-bin/php.cgi/[email protected]&var=value
The relevant components of the PHP symbol table will be:

    $argc       = 4
    $argv[0]    = abc
    $argv[1]    = def
    $argv[2]    = [email protected]&var=value
    $EMAIL_ADDR = [email protected]
    $var        = value

Here is a tip to save the bandwidth rainforest.  There is no reason to
send meta tags to Mozilla compatible browsers.
<?php
if(!strstr($HTTP_USER_AGENT, "Mozilla")) {
?>
  <meta name="author"
        content="I, me and myself" />
<? } ?>

Actually, you can use other chars (including spaces) in the variable name,
if you are using variable variables. E.g., the following works for me (in
PHP 4.1.1):

$x="blah blah-blah";
$$x="value";
echo "var==" . $$x;
echo "var==" . ${"blah blah-blah"};

Its output is:
var==value
var==value

You can use it also in object variables (properties).

'Here document' syntax is explained under the 'echo' function. Somehow I
always try to find it here... In short:

echo <<<EOD
blablabla
tralala
EOD;

In the example listed above:

<?php
$foo = 'Bob';              // Assign the value 'Bob' to $foo
$bar = &$foo;              // Reference $foo via $bar.
$bar = "My name is $bar";  // Alter $bar...
echo $foo;                 // $foo is altered too.
echo $bar;
?>
 
the documentation above it is somewhat ambiguous:
$bar = &$foo means that $foo becomes the reference for $bar, thus $foo
= "Bob".  As I read it, $bar should've become the reference for
$foo, took me a bit to turn it around.  Just some clarification.

Another way to assign a variable a large amount text without having to
worry about quotes getting in the way is like so:

$aVariable = <<<END
"HEY!"
END;

print "$aVariable";

output:  "HEY!"

Where as this is will produce an error:
$aVariable = ""HEY!"";

<<------------------< Env. Variables >------------------>
If you are looking for an explanation of environment variables, go to 


If you wanted to set environment variables, look into the putenv()
function.

How does one send a variable from a particular page, over a secure network
that uses SSL in order for it to be processed by the web server?

Can someone tell me why this page (www.gbasquare.host.sk/news/news.php)
doesn't work??? Yesterday it worked but today the server has upgraded the
php script and the page doesn't work. Thank you

In 'ghent's comment on the 'above example' I think he confuses the
confusion ;)

Here is the example referred to:

<?php
$foo = 'Bob';              // Assign the value 'Bob' to $foo
$bar = &$foo;              // Reference $foo via $bar.
$bar = "My name is $bar";  // Alter $bar...
echo $bar;
echo $foo;                 // $foo is altered too.
?>

�Reference $foo via $bar�/�Alter $bar�� IS correct, but it is a little
obscure.  Here�s what it means:

$bar is assigned a reference to $foo, thus $bar �references� or points to
$foo which contains the string �Bob�.  Essentially what is happening here
is �Bob� is stored in memory at a particular address.  &$foo returns
that address [where �Bob� is stored].  That address is assigned to $bar. 
So, in the string �My name is $bar�, $bar �uses� the address it contains
to find �Bob� (which is �in� $foo) and thus the string becomes �My name is
Bob�.  When the string is assigned to $bar, because $bar refers to $foo,
it gets assigned to the same address location that �Bob� is stored at,
thus �Bob� is overwritten by �My name is Bob�.  The trick here is to
realize that $bar behaves as if it is $foo, so when something is assigned
to $bar (the alias of $foo), it�s as if it was being assigned to $foo!

After the above script is run, the output will look like this:

  My name is BobMy name is Bob

e.g. both $foo and $bar print the same thing.

In �C++� the same code snippit would look like this:

foo = �Bob� ;
bar = &foo ;
bar = �My name is � + *bar ;

Notice that in C/C++ it is necessary to manually dereference the pointer
(*bar) � PHP does this automagically. 

BTW: You might think that �echo $bar;� would display the address of $foo �
not so!  More PHP automagic ;)

Can I call array items multiply as Perl?

It seems:
$x=array(1,2,3,4,5,6,7,8);
$y=$x[3,1,5,7,-1];