In order to avoid bounce messages and unsolicited registrations, most webapps send automatic activation emails upon user registration, and the account remain inactive as long as it is not activated. Better yet, you can periodically purge your data by removing accounts that have not yet been activated.
Here is a step by step To-Do list for Yii beginners. The list is an advice of what tutorials and documentation you can walk through to get a full understanding of the Yii Framework. These can be a help to learn Yii.
There Is Now A cpasswordhelper Class In system.utils at GitHub
that provides an API to simplify the use of crypt() for password storage.
While this wiki article remains valid, it will in due course be rewritten
to refer to the new class as well as explain how it works.