What is Acceptance Criteria?
Acceptance criteria refer to a set of predefined requirements that must be met for a user story to be completed.
"Conditions that a software product must be accepted by a user, customer or any stakeholder." or "The pre-established standards or requirements a product or project must meet."
Acceptance criteria are a set of statements, each with a clear pass/fail outcome, that specifies both functional and non-functional requirements and apply at the epic, feature, and story levels. Acceptance criteria constitute our "definition of perfect", and by done I mean well done.
Acceptance criteria are also called the "definition of done" because they set the scope and requirements to be executed by developers to consider the end of the user story.