What does a System Design Document describe?

What does a System Design Document describe?

• A. Specifies hardware procurement.
• B. Documents user requirements.
• C. Describes the application and its architecture.
• D. Lists test cases.

Answer: (C)

A System Design Document acts as the blueprint for building the system. It describes the application and how its parts fit together: the main components, their interactions, data flows, interfaces, and deployment considerations. It often includes architecture diagrams, data models, service boundaries, and nonfunctional requirements like performance, security, and reliability. This document gives developers a concrete guide for implementation and helps stakeholders understand how the system will meet its objectives. Hardware procurement, user requirements, and test cases belong to other documents, so describing the application and its architecture is exactly what the System Design Document is for.