Answer 1

In associative array, the keys bear some relation to the value other than representing it's position in the array.
They are suitable when use of numerical indexed arrays.
eg.
<?php
$a=array('name'=>'vinay','email'=>'[e-mail]');
echo $a['name']."<br>";
echo $a['email']."<br>";
?>
o/p :-
vinay
[e-mail]