Non-functional software testing is a type of software testing that focuses on testing the functionality of a software application rather than its code. It is also known as performance, reliability, stress, or usability testing.
Thus, it tests whether an application meets its users’ needs and responds well to different inputs or user actions. Testing for non-functional attributes requires different techniques than functional testing does.
While functional testing tests the logic of an application to ensure that it performs as expected and meets its user requirements, non-functional testing ensures that the product functions as intended in real-world usage scenarios. Read on to find out more about these two types of software testing, what they are and why you should use them!
What is Functional Testing?
Functional testing is used to test the logic of a program by evaluating the behavior of the code without considering the actual implementation details of the program.
It is used to make sure that the program operates as expected and meets its user requirements. It is also known as black-box testing since it does not look at the internal implementation of the code but rather at the inputs and outputs of a system as if it were a black box.
Functional testing is used to test if the application meets its functional requirements. A functional requirement details what a program should do. It describes what the program needs to accomplish without explaining how it should be implemented. It answers the following questions: What does the program do? How does it do that? And why does it do that?
What is Non-functional Testing?
Non-functional testing is used to test the quality of a product in terms of system resources, response time, and external interfaces within specified environments. It is also known as a white-box testing since testers analyze the internal details of the system to see if it has been implemented according to the original design.
Non-functional requirements are the expectations a user has of a product that are not related to functionality.
It answers the question what are the product’s performance, reliability, security, accessibility, and usability expectations. Non-functional testing is not to be confused with quality assurance testing which is a broader term that refers to any type of testing done to ensure a product meets its requirements.
Why Is Functional Testing Important?
Functional testing focuses on testing the functionality of a software application. It is used to test if the application meets its functional requirements. A functional requirement details what a program should do.
It describes what the program needs to accomplish without explaining how it should be implemented. It answers the following questions: What does the program do? How does it do that? And why does it do that?
Functional testing is used to test if a software product has the right functionality to suit your needs. It helps to ensure that software functions as expected and meets its user requirements. It identifies defects or issues within the software and verifies they are resolved.
Why Is Non-functional Testing Important?
Non-functional testing is used to test the quality of a product in terms of system resources, response time, and external interfaces within specified environments. It is also known as a white-box testing since testers analyze the internal details of the system to see if it has been implemented according to the original design.
Non-functional requirements are the expectations a user has of a product that are not related to functionality. It answers the question what are the product’s performance, reliability, security, accessibility and usability expectations.
Non-functional testing is not to be confused with quality assurance testing which is a broader term that refers to any type of testing done to ensure a product meets its requirements.
Bottom line
While functional testing tests the logic of an application to ensure that it performs as expected and meets its user requirements, non-functional testing ensures that the product functions as intended in real-world usage scenarios.
Since non-functional testing deals with real-world scenarios, when done properly it can help prevent the release of faulty software. Functional testing, however, is done in a controlled environment, which means it cannot account for all real-world variables.