Functional software testing vs non-functional testing
Today’s eTestware blog tackles a question our software testing experts must frequently answer. As usual, we will favour brevity over a more detailed dive. This is in the hope that a wider discussion might take place in the comments section below. Now, sit back and prepare to enjoy functional software testing vs non-functional testing…
Functional software testing
This mainly involves black box testing and is used to verify whether or not each function operates in alignment with the requirement spec. The application’s source code is not of concern, with the following process typically adopted:
- Appropriate input is provided for all functionality
- Output is verified
- Actual results are then compared to the expected results
This type of testing can be either manual or automated, with numerous elements checked. These include security, database, user interface, APIs, client / server applications and the functionality of the application under test.
Non-functional software testing
We deploy this testing type to check the non-functional aspects of a software application. These typically include performance, usability and reliability. It is mainly used to test for system readiness as per parameters that are not addressed by functional testing. For example, a frequently adopted non-functional software test is checking how many users can login into a software at the same time.
- Functional testing verifies each function of the software to validate actions
- Non-functional testing verifies usability and reliability etc. to validate the overall performance
- You can perform functional testing manually
- This is very difficult with non-functional testing
- The functional type is based upon customer requirements
- The non-functional type is based upon customer expectations
- We perform functional testing first to describe what the product does; we then use non-functional to describe how the product works.
Now you can confidently enter into a ‘functional software testing vs non-functional testing’ debate. Of course, we have provided more of an overview than a deep-dive here. It makes sense then to speak with our testing experts if you want to know more.