The most popular requirement specification technique is the User Story. And in most cases, a set of Acceptance Criteria (AC) comes along with the story, sets boundaries, and helps the team understand what should be implemented for stakeholders to provide value. We will talk about BDD and Gerkin but in terms of requirements, not test cases.
I want to share my recommendations on how to write proper AC that meets the quality criteria: clarity, consistency, testability, completeness, conciseness, and further down the list. The talk is built based on an analysis of errors/inaccuracies that even experienced business analysts make (revealed by a test task's results, which about 300 business analysts have done).