Should you prefix interfaces with I in C#?

Question

Microsoft suggests you should as a naming convention but Robert Martin in the book Clean Code says that you shouldn't use Hungarian notation anymore as it is outdated and no longer needed. What do people think and do in their own code?

Answer 1

You should use I for interfaces.
Interfaces are shown to the outside world. Being able to differ a class from a interface is important.

Robert Martin talks about variables.

So
Use I for interface
And do not use any prefixes for variables.

According to Robert Martin interfaces are bad any way
https://blog.cleancoder.com/uncle-bob/2015/01/08/InterfaceConsideredHarmful.html

Answer 2

I have a naming convension I stick to. I inherited it from Python's pep8

Basically:
- normal_variables are lowercase. With underscore if more than one word

- temporary variables are a single lowercase letter

- function names use PascalCase and no underscores

- similar functions use the same parameter names

I think this about sums it up🤔