It depends how we design our class.While designing a class We should have the Open-Closed principle in mind .When we are talking about encapsulation we are talking about modification and when we are talking about inheritance we are talking about extending our application then we ,as designers , should choose what we should protect against modification ( using private modifiers in our class ) thus encapsulate our class and what's the open side of our class that is reserved for future extension.(protected membmers).(Think of it as partial concept in .net languages that each class can be separated to different files thus some of them can be extended by the programmer and some others are generated using code generation tools)
