Why prefix C# interface names with an “I”

Question

What is the rationale behind this naming convention?

I don\'t see any benefit. The extra prefix just pollutes the API.

My thinking is inline with Konrad\'s respo

Answer 1

It's either that or add "Impl" to the implementation of the interface (argh). I don't have a problem with the "I", it is the simplest and most straightforward naming for an interface.