What are some common pitfalls that PHP beginners may encounter when working with date and time functions?

One common pitfall for PHP beginners when working with date and time functions is not properly formatting the date or time output. To solve this issue, make sure to use the correct format characters (such as 'Y' for year, 'm' for month, 'd' for day, 'H' for hour, 'i' for minute, 's' for second) when using functions like date() or strtotime(). Additionally, be aware of the timezone settings to ensure accurate date and time calculations.

// Example of properly formatting date and time output
$date = date('Y-m-d H:i:s'); // Outputs the current date and time in the format 'YYYY-MM-DD HH:MM:SS'
echo $date;