PHP comparison operators have == as being equal and === as being identical.

This means that == has to change or convert the type to check if it is equal. An example for this is the code below returns “yes”

$a = 1;
$b = '1';

if ($a == $b) {
    echo "yes";
} else {
    echo "no";
}

Because after type juggling (Int and string) they are equal values.

The following code will return “no”

$a = 1;
$b = '1';

if ($a === $b) {
    echo "yes";
} else {
    echo "no";
}

As 1 being an integer is not the same as ‘1’ which is set as a string.

===is faster to fail the condition. It must be noted that the actual speed gain is so minimal that you won’t even notice it, mere microseconds.

$a = true;
$b = 'yes';

if ($a == $b) {
    echo "yes";
} else {
    echo "no";
}

The code above returns “yes” because variable b is set which means it is true, therefor equal to variable a.