Experiential Perfect Aspect
Experiential perfect aspect is a grammaticalization of the current relevance, at the moment of utterance, of an event or state that occurred prior to the moment of utterance. The event or state is expressed as an experience which happened at least once, without respect to a particular location in time, and which is repeatable.
Bill has been to America.
This example contrasts with the following sentence, which is an example of perfect of result aspect:
Bill has gone to America.