Do you remember the requirements level structure according to BABOK (business, functional, system requirements)?

Yes, the BABOK requirements level structure typically includes three main levels:

1. Business Requirements — describe the goals and needs of the business, why the project is important, and what business problems are being addressed.

2. Stakeholder Requirements — describe what the system should do from the stakeholders' perspective, including the functions and capabilities to be implemented.

3. Solution Requirements — detail the technical and system characteristics, including functional and non-functional requirements necessary for implementing the solution.

This hierarchy helps structure requirements from high-level business goals to specific technical specifications.