Mailing lists
Mailing lists are generally used to send marketing or promotional e-mails to a large group of individuals. Mailing lists software helps us manage our lists of users, performs find and replaces to insert users names and e-mail addresses (and other information) when sending the e-mail, and logs statistics.
E-mailing large groups of users introduces a number of problems for us as website owners. They are as follows:
Many shared hosts limit the number of outbound e-mails that a user can send on a daily or even hourly basis.
We have to be careful to make sure our e-mails don't get marked as SPAM; too many spam complaints and we will face retribution from our server provider; for example, being blacklisted so that all our e-mails are flagged as SPAM. There are numerous e-mail blacklisting services; if you get blacklisted you need to contact the various list maintainers to request removal.
Even with our own dedicated resources, sending an e-mail to a large group of users can take time...