In this video, we review the following concepts:
padding - determines how much space the child widget should have added to make the edge of the parent widget. It does not directly determine the location of the child widget. It only adds space to define borders better.
methods/functions - must be in the same class as the widget. Otherwise, must be instantiated or injected into that class.
Custom widgets - additional widgets do not need the structural widgets as the root widget does. For now, they just need the same structure as the Stateless Widgets.