Functional Testing Vs. Non-functional Testing: Understanding the Difference Between Two
What is Functional Testing?
Functional testing is a kind of testing which establishes that every function of the software operates in conformance with the needed specifications. This testing generally includes black-box testing, and it is not concerned about the source code of the app.
Each functionality of the system is tested by implementing relevant input, checking the output, and analyzing the exact results with the required results. This testing includes checking of User Interface, APIs, Database, security, client/ server applications, and functionality of the Application Under Test. The testing can be executed either manually or using automation.
What is Non-functional Testing?
Non-functional testing is a kind of testing to check non-functional features (performance, usability, reliability, etc.) of a software app. It is explicitly designed to test the readiness of a system as per non-functional parameters which are never addressed by functional testing.
A good example of the non-functional test would be to examine how many people can together login into a software.
Non-functional testing is relatively significant as functional testing and affects user satisfaction.
Functional testing approaches
There is a kind of functional testing approaches, and the best way to assure functional test coverage is a mixture of manual and automated testing.
The general functional testing approaches are black-box testing techniques-wherein the tester does not require to evaluate the internal source code but verifies functionality by testing several input combinations.
Here are some of the standard functional testing techniques:
Installation testing
For web or mobile app, testing conventional installation
Boundary value analysis
Testing of the limits of digital inputs
Equivalence partitioning
Grouping tests concurrently to decrease overlap of similar functional tests
Error guessing
Evaluating where functional concerns are most likely to be discovered and testing these more extensively than other fields
Unit testing
Testing conducted at the most modest level of the software-not how the system is running as a whole, but whether each unit is performing accurately
API testing
Verifies that internal and external APIs are functioning correctly, including data transfer and support
Regression testing
Tests that are presented to confirm that new software modifications did not have opposing influences on existing functionality.
All practical tests have a specific output that is expected of any input. If you enter valid data, then you assume the data to be accepted. All functional tests can be scripted with very clear pass/fail criterion.
Non-functional testing approaches
Non-functional testing can seldom need more creativity, and technical expertise since you are testing what the client demands an overall quality experience.
These are the main non-functional testing procedures:
Load testing
Tests conducted on the simulated environment to test the performance of the system during normal circumstances.
Stress testing
Testing performance when low on sources, such as server concerns or lack of hard drive space on a device
Scalability testing
Checking a system’s capacity to balance with extended usage and to what extent performance is influenced
Volume testing
Testing performance with a high volume of data, not significantly high number of users, but could be one user operating a high-volume assignment, such as a multiple-file upload
Security testing
Tests conducted to reveal how exposed the system is to attacks, and how adequately data is preserved
Disaster recovery testing
Checks on how swiftly a system can retrieve following a crash or significant issue
Compliance testing
Tests of the software system on any set of criteria (whether due to industry guidance or a company’s standards)
Usability testing
Testing if the GUI is compatible and if the app as a whole is instinctive and simple to use
