What are the best practices for converting a specific date into a timestamp in PHP?

When converting a specific date into a timestamp in PHP, it's important to ensure that the date is in a format that can be recognized by the strtotime function. One common format is "Y-m-d H:i:s" (e.g. "2022-01-01 12:00:00"). This function will convert the date into a Unix timestamp, which represents the number of seconds since the Unix Epoch (January 1, 1970).

$date = "2022-01-01 12:00:00";
$timestamp = strtotime($date);
echo $timestamp;