When I started developing Android Applications I could see that a lot of people were using Toast. Toast is a class that can be used to put up messages that fade away and is easy to use. So I can see why it is popular. Toast is an excellent aid for debugging as it works the same on a real device as it does on an emulator. Not that I have not found that logging does occur on both platforms too, but Toast is not cluttered by all kinds of other log entries, or the continuous posting of log entries even after your application may have failed.
You can obviously can tailor the way Toast displays itself. Here is an absolute basic version of a Toast call. Note you can control how long it displays on the screen.
Toast.makeText(???, “THIS IS MY TEXT”,Toast.LENGTH_LONG).show();
??? is the context, like myview.getContext()