The Fundamental Difference Between Functional and Non-Functional Testing
When it comes to software testing, there are two major categories that every test falls into, namely functional testing and non-functional testing. While both these types of testing are crucial for ensuring the quality and effectiveness of software, they differ in terms of their objectives, approach, and outcomes. In this article, we will explore the fundamental differences between functional and non-functional testing.
Functional Testing
Functional testing is the process of verifying whether the software application meets the expected functional requirements or not. In other words, it checks if the software is working as intended and is performing its intended functions without any issues or errors. The primary objective of functional testing is to ensure that the software is reliable, robust, and user-friendly.
Functional testing involves testing specific features or functionalities of the software application such as input/output, navigation, data manipulation, and other functionalities. It uses test cases that are created according to the functional requirements of the software. Functional testing is typically performed by software testers, who test the software application for its functionality, data validation, user interface, and usability.
Non-Functional Testing
Non-functional testing, on the other hand, is the process of testing the software application for its non-functional aspects such as performance, security, reliability, and usability. It focuses on verifying the quality attributes of the software application, which are not related to its functionality but are equally important for its success and performance.
Non-functional testing includes testing the software application for its response time, capacity, scalability, stability, and security. It also includes testing the software for its ease of use, accessibility, compatibility, and user experience. Non-functional testing is typically performed by software engineers, who test the software application for its technical aspects, performance, and other non-functional attributes.
The Bottom Line
In summary, functional and non-functional testing are two crucial types of software testing, which are essential for ensuring the quality and effectiveness of software applications. Functional testing verifies whether the software works as intended, while non-functional testing verifies the software’s non-functional attributes such as performance, security, and usability. Therefore, both these types of testing are equally important and should be performed throughout the software development life cycle to ensure the software’s success and performance.
Table difference between functional and non functional test
| Parameters | Functional Test | Non-Functional Test |
|---|---|---|
| Definition | Ensures that system functions as intended | Ensures that system meets performance and reliability expectations |
| Purpose | To ensure that the intended functionality is delivered as expected | To ensure that the systems performance and reliability meet expectations |
| Test Focus | Features, usability and functional requirements of the system | System’s performance, reliability, security and stability |
| Testing Approach | Verification of expected outcomes vs. actual outcomes with specific inputs | Verifying system’s behavior under stress/load and performance benchmarks |
| Examples | Unit testing, integration testing, system testing and acceptance testing | Load testing, stress testing, usability testing and security testing |