After you have setup your Yii2 advanced application, you now have setup your user authentication for both frontend and backend. However, if you have first logged into frontend, and try to access backend from the same client machine, you see no login screen, but find yourself automatically logged in.
If you want to see a live demonstration of what I mean by "how to send POST data from CActiveForm with a CListView inside" you can take a quiz from here and you will understand. (Link not working due to site maintenance. I will fix it in a few days.)
This Behaviour helps to view time/date/timestamp/datetime from db to local Date / Time / Date Time format and in local Timezone. And save into db in with db timezone and db format. You only need to include this behaviour in models where need this facility.
There are cases that you want more control to your menu
Suppose you want a specific menu with complex css, layout, images.