Classes in C# support abstraction, encapsulation, inheritance, and polymorphism. These are the four basic principles of object-oriented programming. The following code snippet shows the syntax for ...

By using interfaces, you can, for example, include behavior from multiple sources in a class. That capability is important in C# because the language doesn’t support multiple inheritance of classes.

You can't really combine the various scopes that you can apply to a C# member because, I suspect, they wouldn't make sense (what's the scope of a public private method, for example?). However, you can ...