Abstraction - Interfaces are the best examples of 
abstraction .
Encapsulation - Classes are best examples of encapsulation.

Generally we encapsulate what varies & 
we abstract commonalities...

One more thing, You should always subclass for behabiours..
you should never subclass for properties / attributes. If 
only properties vary, then you have got to encapsulate them 
in somewhere else e.g. in a class or in some collection 
object like - Properties in Java / Map 

Hope this helps..