In this chapter, you learned about communicating with your users, not just through a Web browser but through that most vital of modern media, electronic mail.
We weaned you off PHP's mail() function early on by showing you how communications with users can be represented in an elegant class hierarchy. We took this further by creating EmailRecipient and EmailCommunication classes as part of that hierarchy, robust and stable enough for everyday use.
We also showed you how Smarty can play a big part in letting you produce template-driven e-mails, and we hinted at some of the more advanced possibilities for the class framework we discussed.
In the next chapter, you meet some of the most important concepts in building enterprise PHP application sessions and authentication.