Chapter 4. Request and Response Management
Software applications are frequently organized into layers that contain logically related entities. Since layers consolidate and isolate the logic for a particular concern, developers can often standardize behaviors, make isolated changes, or swap out significant functionality without affecting other parts of a system. Layering can also help to facilitate understanding of large and complex systems since you can often focus on the purpose and design patterns used in individual layers rather than trying to comprehend the entirety of a system at once.
Consider the layers that have become common in many applications. The Presentation Layer contains logic that displays information and receives ...