Answer Posted / priyanjan

The core diffrence between abstract class and interface is
that interface does not allow implementation of method but
abstract class allows.

Interface is a bunch of declaration of relevant functions.
In real time projects, interface can used if we have to
implement any framework.for eg, if want to implement the
framework of stack,we can do it by defining the prototypes
of push(),pop(),peek() methods in an interface and then
implementing it by any class.
Abstract classes is useful when we are not
required to implement all methods in our class.for eg,we
have Vehicle class, we want to implement classes for two
wheelars in which hand brake is given and in some vehicles
foot brake are given, then Vehicle class abstract class can
be defined as abstract class and implemention of brake()
can be done in applicable classes.

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