Types of QA Testing in Software Development

Types of QA testing, a.k.a. QA testing methods. What’s it all about and how does it work?

For a software you’ve worked on to be functional and reliable, it needs to go through quality assurance testing. In the world of software development, quality assurance (QA) is more than essential as it assures us the app or service doesn’t contain any errors or faults. So when QA steps in, there are various testing methods that help us test our product deliver it safely to our client.

From manual and automated testing as well as functional and non-functional testing, there’s a wide array of methods used nowadays.

So in this article, we’ll go through these types of QA testing mentioned above that we use for our projects during the software development process.

Manual Testing

We’ll start with manual testing. This method involves putting the tester into a role of a user and checking if all features work properly. When using this method, there’s no using any of the automation tools (that we’ll talk about later on). Manual testing is especially useful in early development stages for exploration scenarios and the assessment of UI/UX elements.

However, there is a downside to this method — it is susceptible to human error. Since manual testing involves people doing the work before the testing goes into the automated phase, it requires more time and can overlook errors that software-driven testing wouldn’t let go unnoticed.

So what are the benefits of this methods? First and foremost, its adaptability as well as real-life human evaluation of the user experience. Also, it’s extremely useful when it comes to testing new functionalities. And finally, this method makes it easier for testers to find faults that are not covered in predefined testing scenarios.

Before the actual production phase, manual testing is used in the User Acceptance Testing (UAT) phase.

Automated Testing

Compared to manual testing, automated testing uses tools and scripts to complete tests — without human interference involved in the process.

Automated testing is your go-to when you need to test more complex software products or services that contain a large number of features or functionalities that get updated often. Something that would take a lot more time if only manual testing was involved, with automated testing, much less time is required.

So what are the pros to use this testing method? It is extremely reliable, faster and more efficient than manual testing, and it helps cut down on the expenses in the long run, given that it is not susceptible to human error as the manual testing method.

Of course, you need specialised tools for this type of QA testing. Some of the most common tools used for automated testing are Postman, Selenium, and JUnit.

Functional Testing

Each software has its specs, and this is where functional testing comes into play. In what way exactly? Before the entire system gets pushed further into production, it does it so by checking the entire system’s functionalities. Functional testing has the purpose of making sure that all features are working properly before the software reaches the end user.

Functional tests are also a system documentation of sorts. Because test cases precisely clarify how software should behave in different scenarios.

Does your software check all the boxes when it comes to user requirements? Functional testing method checks this too.

Why is this testing method indispensable? Because it makes sure the key functionalities work as they should and it helps us get better insights into the end user scenarios. Functional testing can be both manual and automated, but as we mentioned above, automated testing provides better efficiency and is simply a faster method overall.

Here are three types of QA testing that fall into the functional testing category.

Unit Testing

Unit tests help developers identify and fix bugs in their code more easily before they become more serious issues and the software itself becomes more complex. Because, as logic itself dictates, more complex software and later stages of software development equals bugs are harder to fix. Often much, much harder.

A big plus of unit testing is that it also encourages better code design — because code that is tested at the unit level ends up being higher quality, cleaner and more modular.

Examples of unit testing tools are JUnit, Jest, and pytest.

Integration Testing

Integration testing comes after unit testing, and it checks the cooperation between the modules or components of the system that’s being tested. This type of testing can reveal that certain modules, although they work without errors during unit testing, when they get integrated, problems occur.

This testing method therefore ensures that all elements of the software eventually integrate as they should. It can cover three different levels of integration, and these three are: component integration, system integration, and external systems integration.

The latter is important for verifying the integration of external APIs.

Often, the tools for integration testing are similar to the tools for unit testing, but when it comes to integration testing, it takes place in an environment that is as similar as possible to the production phase.

Tools that can be used for this method are Postman, JUnit, TestNG, and Selenium.

Regression Testing

If a particular application receives code changes, it should be retested after these changes to check if the existing functionalities are still working. Why? Because with each new change, there is a chance that it might lead to the occurrence of new errors in the system.

So, the purpose of regression testing is to ensure the stability of the system after it being updated in terms of code, features, etc. As a rule, regression testing is automated, but if the team has a plan to do targeted testing, it can also be done manually.

The importance of this type of testing is that it focuses on system stability. It’s integrated into CI/CD processes, so regression bugs can be ‘caught’ immediately during development — and it aims to reduce the risk of unexpected errors along the way.

Non-Functional Testing

In contrast to functional testing that checks whether our software does what it’s supposed to, non-functional testing methods try to determine how the system works in the context of performance, security, usability and reliability. And that’s why we need to perform the following tests:

• performance testing: how does your software perform and how fast is it?


• security testing: are there any security issues in your software?

Several more testing methods fall into the non-functional testing category. Usability testing has the goal to see how usable or intuitive is your software. Reliability/stability testing tries to find the answer to how your product works during longer times of use and if downtimes or outages happen. Lastly, there’s scalability testing with the goal to see if work volume increase is possible without losing performance score.

These testing methods require tools that assist in testing, such as JMeter and LoadRunner for performance testing, and OWASP ZAP and Burp Suite for security testing.

Below, we’ll cover two of the most common non-functional testing methods, crucial for your software’s success in terms of user experience and profitability — performance and security testing.

Performance Testing

This method already in its name explains what its objective is. To test the performance of a software — based on speed, scalability, response, and stability. The key with this method is that the tested software is under certain type of load, such as number of users, high data amount, etc.

Nowadays, every application or service needs to be as fast and efficient as possible because the user can easily switch to another product that has better performance. And the user does not even need a performance test to understand which application suits them better in that context.

There are several types of performance testing, and the most common are:

• load testing: checks how your software performs under expected load


• stress testing: this test increases the load on the system until the breaking point is reached.


• endurance testing: checks the stability of the system over a longer period of time under a certain load


• spike testing: this testing method tries to see your system’s reaction to a sudden increase in load; in other words — spike

As for the tools, special tools are used for the performance testing method. One of them is Apache JMeter which can create different types of workloads; then there are also other tools like LoadRunner, Neoload and Gatling and k6. These tools allow writing test scenarios in programming languages ​​and integration into the CI/CD pipeline.

Security Testing

The security testing method focuses on protecting an app or service — checking its vulnerability or susceptibility to attacks and unauthorised access.

The main purpose of this type of QA testing is to identify weaknesses in the system — before someone else does. Cyber ​​threats are a harsh reality in today’s world, and that is why security testing is an indispensable part of software testing.

There are several subtypes of security testing:

• vulnerability testing involves automated scanning of the system to detect security vulnerabilities


• penetration testing (pen-test) is a simulation of an actual attack


• security audit checks the system against a list of security checks and standards

The tools used in this testing method include OWASP ZAP and Burp Suite, Nessus, Qualys, among others.

Conclusion

Each of the above QA testing methods has its own objective, its ‘why’ and ‘how’. While manual testing has the advantage of human factor and real-person evaluation, this can also be a disadvantage. To reduce the chance of human error, automated testing steps into the game. In terms of functionality, functional testing ensures the software functionalities are working properly, whereas non-functional testing checks how your system works regarding performance, security, usability and reliability.

Speaking of functional testing, as the lowest level of QA testing, unit testing helps fix errors in the code in the early stages of development, meanwhile integration testing evaluates if all the modules or components of your system work properly together. Has your software had any changes in code? This is what regression testing is for, to decrease the chance of new errors in the system.

When it comes to non-functional methods, this is where performance testing proves to be essential as it checks your software is ‘all good’ in terms of speed, scalability, response, and stability. On the other hand, security testing helps ensure your product is secure and non-susceptible to any kind of threat or external attacks.

We cover all these methods in our portfolio. Feel free to contact us, and see how we can make your software reliable, prone to different types of threats, and functional for your end users.