The following pattern checks whether the input string is a valid email address in the form "firstname.lastname@example.org". Actually, it does not have to be a ".com" address. Any combination of letters following the last period are fine. Also, the email name can have a dash or be separated by one or more periods. The Domain name can also have multiple words separated by periods. Thus, it will validate email@example.com and firstname.lastname@example.org.