How can one convert a timestamp back into a readable date format in PHP?

To convert a timestamp back into a readable date format in PHP, you can use the `date()` function along with the timestamp value and the desired date format string. This function will convert the timestamp into a human-readable date format that you specify.

$timestamp = 1609459200; // Example timestamp
$date = date('Y-m-d H:i:s', $timestamp); // Convert timestamp to date format
echo $date; // Output: 2021-01-01 00:00:00