It is difficult to estimate the role of testing in the process of software product development. Its goals are not limited to fixing bugs. The basic idea behind software testing is not only to make sure a product works as intended but also to determine the likelihood of a negative user experience in the future. To make this happen, specialists use a lot of different testing methods, which are easy to get confused. In this article, we'll look at the most popular types of software testing to fill in the gaps.
Manual and Automated Testing
Let’s get started with a simple classification based on how tests are performed. Of course, we're talking about manual and automated testing.
In manual testing, the tests are performed manually by a QA specialist. A tester checks the basic features of a product, executing the test cases, and generating the test reports without the help of any automated tools. This type of testing may seem outdated at first glance, but it has its advantages. First, manual testing is cheaper because you don't have to pay for extra tools. Second, the human eye always gives the best output when it comes to user experience. Machines can find errors in the functioning of a product, while the person can tell you what extra problems a user may have when interacting with it.
Automated testing is executed by automated tools. Testers write code scripts that are programmed to test a particular part of the system. An automated tool checks whether the actual result matches the expected result. It also helps automate repetitive tasks. Test automation significantly saves time and minimizes the possibility of human error, which is why more and more software development companies are moving toward automated testing methods. However, this type of testing also has its weaknesses. For example, it does not help gain user insights, and its capabilities are always limited by the written script.
Functional and Non-Functional Types of Software Testing
As stated, testing is extremely important at every stage of software development. Whether you create a design or write a code for a new feature, a tester will help you choose the right direction, promptly finding weaknesses without accumulating issues. Based on the goals of testing, there are two broad areas of functional and non-functional testing. Each type has its subtypes.
Functional testing is intended to check the functional perfection of the system, whether all features work correctly, whether they meet the requirements described in specifications. This type of testing will allow you to simulate the actual use of a product and find defects in its work. Functional tests are performed both manually and using automation tools. This type of testing includes the following subtypes.
- Unit testing
Unit tests are aimed to check the source code of individual system modules. Unit tests are usually run by developers, not testers, as they require deep programming knowledge. By running unit tests, you find out whether the functions of the classes, components, or modules used by your software work correctly. The basic idea of unit testing is to write tests for each separate function or method in order to quickly check whether the latest changes in the code have not led to the appearance of errors in the already tested parts of the program.
- Integration testing
When adding new modules to a system, we need to make sure that all modules work well together. This is where integration tests come in. This type of testing helps you build a robust software system that is flexible and responsive to changes. An example of an integration test is testing the interaction of a product with a database. Such tests significantly reduce the time to find bugs and allow you to fix them before moving on to the next development stage.
- End-to-end testing
End-to-end testing means testing the entire system. The main purpose of end-to-end testing that simulates the real work of your product is to see how your app or platform behaves in real life. With this type of testing, QA specialists verify that user flows work as expected. For example, we check a subscription form to make sure that the whole process is right, so a user can enter his email, the data will go to the database and trigger automatic mailing, the user will see a message about a successful subscription or receive an email, and so on.
- Interface testing (UI tests)
As the name suggests, interface testing involves testing the user interface of the application, its compliance with specifications. Here, specialists check whether the application is displayed correctly on different devices, how different elements react to user actions, whether there are structural and visual flaws in the interface. UI tests help make the user interface of your product more user-friendly and effective for both the user and the owner of the software product.
- Regression testing
Regression testing is the detection of bugs in already tested areas of the product to make sure that fixed bugs do not reappear when the code is changed again. In other words, the goal of regression tests is to verify that fixing some bugs does not cause others to appear. They also ensure that changes in the new version of the application do not damage the existing functionality of the product.
- User Acceptance testing
Before releasing a product, you need to know exactly how it behaves in real life. User acceptance testing is testing from the user's and the client's perspective. Running user acceptance tests, specialists conduct a final assessment of the product's work, whether it turned out the way it was intended. Good test results confirm that the product has reached the required quality. The acceptance testing phase lasts until the customer makes a decision to send the application for revision or launch it.
The correct operation of software functions doesn’t guarantee that the product will be ideal for the user. There are many other properties that affect user engagement and convenience of working with the software. This is where non-functional testing comes in. This type of testing is designed to check the non-functional properties of a product, such as usability, reliability, performance, and others. Functional testing describes what a product does, while non-functional testing describes how a product works. Non-functional testing also has its own subtypes.
- Documentation testing
Documentation is an important part of any software product. It describes how a product works and what to expect from it. Documentation testing is meant to make sure that the documentation is correct and matches what the system actually does. It is about testing all documents that explain and confirm the requirements, as well as the procedures performed and the expected results.
- Installation testing
Installation testing is another way to check whether a software product is ready for use. Using this type of testing, QA specialists check the correctness of the installation and configuration of the software. Errors can occur when updating to a new version, due to poor design of system requirements, and more. Installation testing helps to ensure that the software starts with correct work and protects against data loss during updates.
- Reliability testing
The reliability of software is measured by whether a system will perform correctly in a specific environment and for a specific period of time. In other words, the purpose of reliability testing is to verify that a software product will perform as intended under the required load. For this goal, testers determine whether there are data leaks (stability testing) and how long it takes for the system to recover from failure (recovery testing).
- Security testing
It is not hard to guess that security testing is carried out to check the security of the system, to protect a product from viruses and hacker attacks. To do this, specialists check software for known types of vulnerabilities, such as XSS (Cross-Site Scripting), XSRF/CSRF (Request Forgery), Code injections (SQL, PHP, ASP), Server-Side Includes (SSI) Injection, and others.
- Performance testing
The main property of performance testing is that you can only run it after a full functional check. Performance testing is designed to determine the speed of the system under the required load. It consists of other testing subtypes:
- Load testing is produced to learn the behavior of a product under the expected load.
- Stress testing is designed to check the stability of a system in extreme conditions.
- Endurance testing is done to make sure a product can handle the expected load, to identify memory leaks, and to ensure that the processing speed and response time of the system at the beginning of the test do not decrease over time.
- Spike testing is testing how a system performs in the face of rapidly increasing and decreasing user load. It helps prevent problems with speed, stability, and scalability of the software.
We can go on and on discussing the types of software testing. Depending on the purpose of the testing and the type of software product, a huge number of tests can be performed to ensure that the software product meets the requirements and expectations of users. Some types of testing are carried out manually, some are automated, but most often they are mixed. Now when you know all the basic types of software testing, you know what to expect from the testing process while developing your app. You may not need all types of testing, but keep in mind that you shouldn't skip this step altogether. As Aristotle said, quality is not an act, it is a habit.