Functional requirements and non-functional requirements are two different types of requirements that are often defined during the system design process.
Functional requirements are requirements that describe the specific features and functions that a system must have in order to meet its goals. These requirements define what the system should do, and are typically related to the specific tasks that the system is designed to perform. Examples of functional requirements might include:
The ability to add items to a shopping cart The ability to search for products by keyword The ability to process payments through a third-party payment gateway
Non-functional requirements, on the other hand, are requirements that describe how the system should perform. These requirements are not related to the specific features and functions of the system, but rather to its overall performance, security, and usability. Examples of non-functional requirements might include:
Response time: The system must respond to user requests within 2 seconds. Scalability: The system must be able to handle a large number of users simultaneously without slowing down. Security: The system must protect user data from unauthorized access or disclosure.
Here is an example to illustrate the difference between functional and non-functional requirements:
Suppose a company is designing an e-commerce website. The functional requirements might include:
The ability to browse products by category
The ability to add products to a shopping cart
The ability to process payments through a third-party payment gateway
The non-functional requirements for the same e-commerce website might include:
Response time: The website must load pages within 3 seconds.
Scalability: The website must be able to handle 10,000 simultaneous users.
Usability: The website must be easy to navigate and use for users of all skill levels.
In summary, functional requirements describe what a system should do, while non-functional requirements describe how a system should perform. Both types of requirements are important for designing a system that meets the needs of its users and performs effectively.