# Auth Components

Authentication is a fairly complex topic, but like most complex topics it can be broken down into smaller parts.

## ActiveRecord validations

* What are different types of validations?
* Which ones could be useful?
* Describe 3 use cases.

## ActionController filters?

* What is an ActionController filter?
* What are different types of ActionController filters?
* Describe 3 use cases of filters.

## has\_secure\_password

* What is `has_secure_password`?
* How does it work (in Rails)?