There are two views in the Application Explorer. The first view, called classic view, displays all the elements from all the models grouped according to type, while the second view, called model view, displays each model separately. When you expand a particular model, it displays elements from that model grouped according to type. 

The following image shows the classic and model views of the application explorer in Visual Studio. To switch between these views, you can right-click on AOT and switch between them: