In the new android studio version there is a new big change. I read the documentation about "Implement navigation with the Navigation components" but can somebody explain to me which is the main difference between this method and the classic one?
The navigation architecture component is part of JetPack is a new way to navigate your app.
The main different is that before you have multiple activities in your application -still you can- to move to different content areas in your app, now with the nav arch component you can have only one activity and the rest of the features of your app is based on fragments, keeping the single activity as a the main container.
In this link Ian Lake the creator of navigation architecture explains why we should use this approach.
Also, here is the guide to Navigation Architecture
https://developer.android.com/topic/libraries/architecture/navigation/
Give a look at these resources.
Best regards.
Pedro Varela