PHP basics

1.  In PHP 0 and FALSE are same when you will use == operator but not same when you will use === operator.=== operator checks the type and value so use === operator to check whether a function returns FALSE or not specially in case of those built in function those return FALSE in case of not finding desired result (e.g : stripos).
stripos returns FALSE if it can not find the desired needle in the haystack. so consider the following example.
//////////////////////////////
$haystack = "Basics of PHP";
$needle ="Basics";
if(stripos($haystack,$needle)==false)
echo "Match found";
///////////////////////////
This will output "Match found";
But the output should have been given if the the needle was not in the haystack. But since the needle (in this case "Basics") was in the 0 position of the haystack the stripos is returning 0. and we are using == operator . that means here false and 0 becomes same.
But if the code was like this
//////////////////////////////
$haystack = "Basics of PHP";
$needle ="Basics";
if(stripos($haystack,$needle)===false)
echo "Match found";
///////////////////////////
This will not output anything.