PHP

integer data type php

/*Integer data types are non-decimal numbers BETWEEN -2147483648 and 
2147483647 in 32 bit systems, and between -9223372036854775808 and 
9223372036854775807 in 64 bit systems. A value that satisfies both of these
conditions is a integer in php
*/

PHP Data Types

<?php
$x = "Hello world!";
$y = 'Hello world!';

echo $x;
echo "<br>";
echo $y;
?>