So, in this case, you are extending the functionality of an object with functionality of another object.
After studying this cookbook page you are encouraged to reread the [corresponding guide page](http://www.yiiframework.com/doc/guide/basics.component) as it contains advanced information (for example, if you are familiar with interfaces, you might find it enough to implement IBehavior before extending CBehavior).
- Russian version: [Поведение и события](http://phptime.ru/blog/yii/31.html)