What are the key differences between BRD (Business Requirements Document) and FRD (Functional Requirements Document)?

The key difference between a BRD (Business Requirements Document) and an FRD (Functional Requirements Document) is that a BRD outlines the overall business objectives and goals of a project, while an FRD details the specific functions and features that the system or product must have to meet those objectives. In other Words, the BRD focuses on the "what" of the project, while the FRD focuses on the "how."