How does PHP internally handle the comparison of date strings, and what functions or methods are involved in this process?

When comparing date strings in PHP, it is important to ensure that the dates are in a format that PHP can understand and compare accurately. One way to do this is by converting the date strings into DateTime objects using the DateTime class in PHP. This allows for easy comparison of dates using the comparison operators like greater than (>), less than (<), or equal to (==).

$date1 = new DateTime('2022-01-01');
$date2 = new DateTime('2022-01-15');

if ($date1 < $date2) {
    echo "Date 1 is before Date 2";
} elseif ($date1 > $date2) {
    echo "Date 1 is after Date 2";
} else {
    echo "Date 1 is equal to Date 2";
}