The C# interface isn’t exactly intuitive. Interfaces, in general, are common. We use them all the time. You’re using at least one interface right now as you read this article. Keyboards, mice, and screens are interfaces to your operating system. It’s the same concept with C# interfaces. In this article, I’ll start with these familiar device interfaces as a metaphor for explaining the C# interface. I’ll use examples and alert you to some of the pitfalls. You’ll also learn about industry best-practices when using C# interfaces. By the end, you should have a clear picture of the C# interface.