Testing techniques in software testing

Posted in: Quality assurance testing by: Simon on:

With software applications becoming more complex and the global number of browsers and devices combinations skyrocketing, comprehensive testing has never been more important; however, a lot depends on your ability to pair the right technique with the right application. The following guide to software testing techniques will hopefully help you acquire a better understanding of this often misunderstood process.

Software testing methods

The three primary software testing methods are known as Black Box, White Box and Grey Box testing. Here is a brief overview of each one.

Black Box

With this method, testing is conducted without any knowledge of the software’s source code or system architecture. While this blind approach can be rather inefficient it ensures that testing is conducted from a user-perspective rather than that of the program designer.

White Box

This method implies that the tester has access to application’s architecture and source code. This enables testers to dig deeper into products and identify issues and their causes more easily.

Grey Box

A mix of the Black and White Box methods, Grey Box testing is conducted with limited access to the internal workings of the program. For instance, while testers may have access to the architecture and the database they may not have access to the source code.

Software testing techniques

Apart from embracing a Black, White or Grey Box approach, software testing techniques can be described as being either functional or non-functional. Let’s dive in and take a closer look.

Functional Testing

Ensuring that an application functions according to its design specifications is obviously rather important and functional testing does just that via a series of four vital tests:

  • Unit testing – Often described as the backbone of software testing, unit testing examines the individual components of a software product. Testing is done in isolation, usually for a single function.
  • Integration testing – Once the individual components have been tested, integration testing evaluates their ability to work well together.
  • System testing – This is the “big picture” testing. These tests consider the hardware and software components of the entire system to ensure it is free from bugs and errors in a near-final environment. Here testers will want to consider the expected user behaviour as well as edge cases.
  • Acceptance testing – This final round of testing is conducted by the client(s) to ensure that all project requirements have been met and that the software operates the way it is expected to.
  • Compatibility testing – Examines a program’s ability to work with a wide variety or browsers, platforms, operating systems and devices by testing as many combinations as possible.

Non-functional testing

Rather than testing specific functions, non-functional testing examines a program’s readiness by focusing on defined technical capabilities, such as scalability, usability and vulnerability. There are dozens of types of non-functional testing, here are the ones you’ll hear about most commonly:

  • Performance testing – Confirms that a program operates quickly and reliably enough to meet pre-determined criteria, with scalability, reliability and resource usage often a major focus.
  • Security testing – Ensures that the system is protected against unauthorized access by testing for confidentiality, availability, integrity, authentication and non-repudiation.
  • Usability testing – Evaluates software by inviting “real” users to try it. It takes into account five main factors impacting a user’s ability to fully utilise the software, which are efficiency, satisfaction, learnability, memorability and errors.
  • Localization testing – These tets are done to ensure that all of the text used in the application has been successfully translated in the language and culture of your audience.

Of course, there are many more testing techniques and these are simply the common ones. A healthy combination of all these techniques is key to publishing a great software product; but your company and your project’s context dictate what techniques are best suited to your projects. Remember to always push as more tests and more diverse tests before your big launch!



Simon is the founder of Crowdsourced Testing. After 10 years in interactive software development, he set his sights on building a world-class crowdsourcing platform to facilitate the software testing process for developers.