What are the differences between abstraction and interfaces?

Question

Accepted Answer

Abstraction is hiding implementation details while interface defines a contract for communication.

Abstraction is achieved through abstract classes and interfaces.
Interface only contains method signatures while abstraction can have both method signatures and implementation.
Abstraction is used for reducing complexity and increasing reusability.
Interface is used for achieving multiple inheritance and loose coupling.
Abstraction is a concept while interface is a language construct.

Accepted Answer

Abstraction contains Declaration and definition . Interface only contains Declaration Part. Multiple Inheritance is not achieved by Abstraction but In Interface, we can use multiple inheritances. Abstract class contains constructor and Interface does not have that. Static members are contained. The interface does not contain Static Members. A class can use only one Abstract Class. A Class can use multiple Interfaces.

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What are the differences between abstraction and interfaces?

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