Difference between a Business Requirement Document (BRD) and Functional Specification Document (FSD)
Purpose:
BRD: Describes the high-level business needs, goals, and objectives of a project or system. It focuses on “what” the system must do to meet the requirements of the business.
FSD: Outlines the detailed functionality and features that will be supported by the system. It focuses on “how” the system will accomplish the requirements laid out in the BRD.
Content:
BRD: Contains business requirements, project deliverables, inputs, outputs, and the needs and expectations of the customer. It provides an overall understanding of what the business wants to achieve.
FSD: Defines the logical behavior of the system, expressed as services, tasks, or functions. It captures the intended user experience and interaction with the system.
Authors:
BRD: Typically prepared by the project manager or business analyst.
FSD: Usually written by the business analyst or systems analyst.
Scope:
BRD: Covers the broader business objectives, constraints, and desired outcomes.
FSD: Focuses on the specific functionality and features required to fulfil the business needs identified in the BRD.
Level of Detail:
BRD: Provides a high-level overview of the project, without going into technical specifics.
FSD: Offers a more detailed description of how the system will function, often including screen mock-ups or wireframes to communicate the system’s layout and design.
An FSD is derived from the BRD, as it outlines the functions necessary to fulfil the business requirements. Overall, the BRD sets the stage by identifying the business needs and goals, while the FSD elaborates on how those needs will be met through specific system functionality. The BRD focuses on the “what,” and the FSD focuses on the “how.”