PHP is equal to or not equal to one exclamation mark and two equal signs

$a == $b equals TRUE if $a equals $b.
$a === $b Congruent TRUE if $a is equal to $b and they are of the same type. (Introduced in PHP 4)
$a != $b is not equal to TRUE if $a is not equal to $b.
$a <> $b is not equal TRUE if $a is not equal to $b.
$a !== $b non-congruent TRUE if $a is not equal to $b, or their types are different. (Introduced in PHP 4)
$a < $b is less than TRUE if $a is strictly less than $b.
$a > $b is greater than TRUE if $a is strictly $b.
$a <= $b is less than or equal to TRUE if $a is less than or equal to $b.
$a >= $b is greater than or equal to TRUE if $a is greater than or equal to $b.