Does Changing The Configuration Kill The App And Restart It?

I was reading This Tutorial section 6.1. And it says that, changing the configuration of an App causes the App to Restart? My question is, in what sense the App would Restart? does

Solution 1:

The app is not killed an restarted.

Your Activity will, however, be recreated.

If you think about how an Activity's layout can be changed when the device is rotated, this makes sense. If you have a portrait layout in your layout/ folder and and landscape layout in your layout-land/ folder, then Android will need to destroy the Activity and recreate it with the new layout.