Functional vs Non Functional Requirements
The Key Difference Between Functional and Non functional Requirements is that Functional requirements describe what the system or software is supposed to do, whereas Non-Functional requirements describe how the system or software should perform.
- Functional and Non functional Requirements both have different features and functionalities, here is a comparison of some key features between them.
|Functional Requirements||Non Functional Requirements|
|Functional requirement describes what a software system should do.||Non-Functional requirements describe how the system or software should perform|
|Functional requirement is specified by User.||Non-functional requirement is specified by technical persons.|
|Functional Requirements is mandatory.||Non Functional Requirements is not mandatory.|
|Functional requirement is describing the behavior of the system as it relates to the system’s functionality.||Non-functional requirement elaborates a performance characteristic of the system.|
|Verify the software’s functionality||Verify the software’s performance|
|Functional testing such as API testing, system, integration||Non-Functional testing such as usability, performance, stress, security, etc|