Usually, I want to make the name of my interface the cleanest possible name. In that case, my interface would be named "Widget". Then, if it makes sense, I migh

Usually, I want to make the name of my interface the cleanest possible name. In that case, my interface would be named "Widget". Then, if it makes sense, I might have a partial implementation that works for many cases - I would probably call that WidgetBase. Actual implementations of the widget would try to have a name related to what makes them different than the others - maybe Button, TextBox, etc. Those implementations might inherit from WidgetBase if it makes sense, or just implement the interface. At any rate, WidgetBase is only ever referenced by subclasses - the users of the widget code would either depend on "Button" or "TextBox" specficially, or the "Widget" interface for more generic handling. WidgetBase is really just there for convenience, and you could remove it if it turns out not to be as useful as you thought.