Functional requirements in software engineering describe what a software system must do to satisfy user needs. They define the specific functions the software must perform, the data it must process, and the outputs it must produce.
Think of them as the "what" of the software system – they outline the core functionalities users expect.
Here's a breakdown of key aspects:
1. Focus on Functionality:
- What the system will do: Functional requirements detail the specific actions the software should perform. For example, in an e-commerce website, a functional requirement might state: "The system must allow users to add items to their shopping cart."
- Data processing: They describe the data the software will handle, including input, processing, and output. For example: "The system must store user account information, including name, email, and address."
- Outputs and interactions: Functional requirements define the outputs the system will produce, such as reports, notifications, or user interfaces. An example could be: "The system must generate an order confirmation email upon successful purchase."
2. User-Centric Perspective:
- Functional requirements are driven by user needs. They are derived from understanding how users will interact with the software and what specific tasks they need to accomplish.
- They focus on user experience and ensure the software meets their expectations.
3. Examples of Functional Requirements:
- For a social media platform:
- "Users must be able to create a profile."
- "Users must be able to post text, images, and videos."
- "Users must be able to follow other users and receive notifications."
- For an online banking application:
- "Users must be able to check their account balance."
- "Users must be able to transfer funds between accounts."
- "Users must be able to pay bills online."
4. Importance of Functional Requirements:
- They serve as the foundation for software development.
- They provide a clear understanding of what the system should achieve.
- They help developers design and build the software effectively.
- They ensure the final product meets user expectations.
By defining functional requirements, software engineers ensure that the software system performs as intended and meets the needs of its users.
