What is the recommended format for storing times in a PHP application to facilitate easy calculations and comparisons?

When storing times in a PHP application for easy calculations and comparisons, it is recommended to use the Unix timestamp format. This format represents a point in time as the number of seconds that have elapsed since January 1, 1970. By storing times as Unix timestamps, you can easily perform calculations, comparisons, and conversions without worrying about time zones or daylight saving time changes.

// Storing current time as a Unix timestamp
$current_time = time();

// Storing a specific time as a Unix timestamp
$specific_time = strtotime('2022-01-01 12:00:00');

// Calculating the difference in seconds between two Unix timestamps
$time_difference = $specific_time - $current_time;

// Converting a Unix timestamp to a human-readable date and time
$converted_time = date('Y-m-d H:i:s', $specific_time);