What is the need to introduce interfaces when we already have our own super-set abstract classes?

Question

Abstract classes contain both types of methods - abstract (not implemented), as well as specific (implemented) methods. Although the interfaces contain only not implemented methods. This means that interfaces are a subset of abstract classes. Then why were the interfaces introduced in C # (.Net)? In my opinion, there are two reasons for this:

• To support multiple inheritance
• Support inheritance for value types (structs) in C #.

Is there any other reason or some hidden concept that I am missing?

Answer 1

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