Use of I as personal pronoun in interface names

Question

Back in my COM days, it was common to use the I in interface names as a personal pronoun, as if the object was describing what it could do. ie:

IProvideData

Is this still the case in the world of .Net, or it is now preffered to use the third person:

IDataProvider

Answer 1

Quoted from the naming guidelines:

Do name classes, interfaces, and value types with nouns, noun phrases, or occasionally adjective phrases

Given that, IDataProvider seems like a better name than IProvideData. I find it more logical, especially when paired with member names. IDataProvider.GetData seems more natural to me than IProvideData.GetData.

Read more in Names of Classes, Structs, and Interfaces in the Design Guidelines for Developing Class Libraries.