Why does this not return true?

when I use this code and pass the uId of 55 I expect it to return “cool”.

but I get “not” when I type

[color=#0000ff]http://myurl.com/test.php?uId=55[/color]

any ideas.

 
<?php 
 
$uId = $_GET['uId']; 
 
function Secure(){ 
if($uId == 55){ 
return true; 
} 
} 
 
if(Secure()){ 
echo "cool"; 
}else{ 
echo "not"; 
} 
?>