In what scenarios should mktime() be used in PHP for time-related operations?

The mktime() function in PHP should be used when you need to create a Unix timestamp based on a specific date and time. This is useful for performing time-related operations such as calculating differences between dates, determining future or past dates, or converting dates to timestamps. By using mktime(), you can easily manipulate dates and times in PHP.

// Example usage of mktime() to create a Unix timestamp for a specific date and time
$timestamp = mktime(12, 0, 0, 10, 15, 2022); // Creates a timestamp for October 15, 2022 at 12:00:00 PM

echo $timestamp; // Output: 1665892800 (Unix timestamp for the specified date and time)