In scrum, user stories are one of the best and most popular form of creating a shared understanding of what the user of a system wants to accomplish.
User stories consist of 3 parts:
The “card” is a high level description of what the user wants, usually taking the form of “As a <type of user> I want <some functionality> so that I can <achieve some kind of goal>”
The purpose of this conversation is to create a shared understanding of the expected outcome of implementing the story.
The “confirmation” is the additional detail captured during the “confirmation” that confirms the details, expected outcomes, acceptance criteria, or anything else that was discussed and agreed upon during the conversation.