How do the different layers in an architecture based on the principles of clean architecture interact?

In clean architecture, layers are separated by responsibility and interact strictly through defined interfaces, which ensures loose coupling and ease of testing.

Main levels:

• Entities — business logic and rules.
• Use Cases — usage scenarios, implement business logic.
• Interface Adapters — transform data between layers, e.g., presenters, controllers.
• Frameworks & Drivers — UI, databases, networks.

Interaction occurs from outer layers to inner layers through interfaces. Inner layers do not depend on outer layers, and outer layers only know about the interfaces of inner layers.

For example, the UI calls methods of interactors, which work with entities. The result is passed back through adapters, which format data for display.

This allows changing the UI or database without modifying the business logic.