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Different Types of Software Testing: A Comprehensive Guide

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Praise Iwuh

June 16, 2023

Different Types of Software Testing: A Comprehensive Guide

Software testing is a phase in the software development lifecycle (SDLC) that determines if the code written executes the desired or specified actions. It is such a complex topic that sometimes runs in so many circles, and you end up with more questions than answers; manual vs automated testing, dynamic vs static testing, functional vs non-functional testing, etc.

This article will explain the different methods, types and forms of software testing.

What you will learn

What are the types of testing?
Functional
Non-Functional
Dynamic vs Static Testing
Manual vs Automated Testing
Other testing subtypes
Final thoughts

What are the types of Software Testing?

Cutting to the chase, Software testing can be classified into functional and non-functional testing. Functional testing is tasked with verifying that the software functions correctly and meets the specified requirements. It involves testing the individual functions and features of the software to ensure they work as intended.

On the other hand, non-functional testing focuses on evaluating the characteristics of the software that are not directly related to its functionality. This type of testing includes aspects such as performance, security, usability, reliability, and compatibility testing.

Some other forms of testing which we always encounter and sometimes confuse for the types of testing are actually approaches to and methods of testing, such as static and dynamic testing or manual and automated testing. We’ll discuss those further down the article as well.

Functional Testing

Functional testing checks whether a software system meets its specified functional requirements. It focuses on the system’s behaviour and functionality from the user’s perspective, testing each function of the application by providing appropriate input and verifying the output against the functional requirements. Functional testing involves the following methods: It encompasses various levels of testing, including unit testing, integration testing, system testing, and acceptance testing. Each testing level contributes to the software system's overall validation and verification.

Unit Testing

A unit is the smallest testable part of a system or application. Unit testing determines the correctness and functionality of these individual components, which could be a function, method or class, ensuring that they perform as intended and meet the specified requirements. Because developers do unit testing in the application development stage, it helps identify defects early and provides assurance in the competence of individual units.

Integration Testing

Once individual units have been thoroughly tested, integration testing comes into play. Integration testing focuses on testing the interactions and compatibility between different components or modules of the system. It verifies that the integrated components work together seamlessly and that data flows correctly between them. It helps detect defects that may arise when components are combined and validates the overall functionality of the integrated system.

System Testing

After integration testing, system testing is performed to evaluate the system as a whole. System testing involves testing the complete and integrated software system against the functional requirements and specifications. It examines the system's behaviour in different scenarios, tests its functionality from end to end, and verifies that it meets the desired user requirements. System testing helps ensure that the software system performs as expected in a real-world environment.

Acceptance Testing

Acceptance testing is the final stage of functional testing and is typically conducted by stakeholders or end users. It aims to determine whether the software system meets the specified business requirements and is ready for deployment. Acceptance testing confirms that the system fulfils the intended purpose, complies with user expectations, and satisfies contractual or regulatory obligations. It provides assurance that the system is acceptable for use in its operational environment.

Non-Functional Testing

Non-functional or quality attribute testing evaluates a software system's performance, usability, security, compatibility and other non-functional aspects. Unlike functional testing, which verifies the system's behaviour and features, non-functional testing assesses the software's performance in different conditions and environments.

It encompasses various types of testing, including security, performance, usability, and compatibility. Each one of these testing techniques addresses specific non-functional aspects of the system to ensure it meets the required standards and user expectations.

Security Testing

Security testing aims to identify vulnerabilities and weaknesses in the software system's security mechanisms. It involves testing the system's ability to protect data, prevent unauthorised access, and withstand potential attacks. Security testing includes measures such as penetration testing, vulnerability scanning, and testing authentication and authorisation processes, identifying and addressing security flaws to safeguard a system's integrity and sensitive information.

Performance Testing

Performance testing evaluates the system's performance and responsiveness under various conditions. It tests the system's ability to handle expected workloads, process transactions efficiently, and respond within acceptable time frames. Performance testing includes load, stress, and endurance testing to assess the system's scalability, stability, and resource utilisation. Performance testing identifies performance defects, optimises system performance, and ensures a satisfactory user experience.

Usability Testing

Usability testing focuses on evaluating the system's ease of use and user-friendliness. It assesses how well users can interact with the system, understand its functionalities, and accomplish their tasks effectively. Usability testing involves observing users' interactions, collecting feedback, and analysing user satisfaction. By conducting usability testing, you can identify usability issues, improve the user interface, and enhance the overall user experience, ultimately increasing user adoption and satisfaction.

Compatibility Testing

Compatibility testing ensures that the software system functions correctly across different platforms, operating systems, browsers, and devices. It verifies that the system maintains its intended functionality and appearance irrespective of the variations in the computing environment. Compatibility testing involves testing the system on various configurations, performing cross-browser testing, and verifying compatibility with different hardware or software configurations. It ensures consistent user experience across diverse environments and minimises compatibility-related issues.

Manual vs Automated Testing

Manual and automated testing are two basic methods of software testing, each with its unique characteristics and advantages.

Manual testing, as the name implies, involves using human effort, experience and knowledge to uncover vulnerabilities. It is often done by a team of security professionals who execute test cases step by step and carefully observe the software's behaviours, scouring the application for bugs that usually escape automated scanners. It utilises human guile and intuition, which computers are still incapable of, combined with domain knowledge to identify potential issues.

On the other hand, automated testing uses testing software to find and report vulnerabilities automatically. These specialised software tools execute predefined test cases, simulate user interactions, and compare the actual results with expected outcomes. Automated testing detects a wider range of issues and performs repetitive tasks efficiently and consistently, reducing human effort and saving time. Automated testing is better suited for large-scale code analysis, as it can handle high-volume test cases and provide faster feedback on the software's behaviour.

You can get a better result by blending both methods, usually in the order of automated first to discover a multitude of errors and manually to identify the few which got past the automated scanning.

Dynamic vs Static Testing

Often misrepresented as types of testing, these are better defined as approaches to software testing rather than methods or types. They overlap different testing methods and are directly parallel to each other. To take a closer look:

Dynamic Testing

Dynamic testing is an approach to software testing that involves executing the software and observing its behaviour in various scenarios. It focuses on evaluating the software's functionality, performance, reliability, and other aspects in a dynamic environment, or simply put, while it is being run. It is done to identify defects, errors, and vulnerabilities that may not be detectable through static analysis alone. Dynamic testing may be manual or automated and involves various testing techniques, including both black-box and white-box testing, grey-box testing, and regression testing.

Static Testing

Static testing is the opposite of its dynamic counterpart. It analyses software applications or components in a dormant environment. This means reviewing the code before it is executed. It aims to identify bugs, errors, and issues very early in the development life cycle. Static testing helps ensure the software's quality, reliability, and maintainability by detecting problems before they manifest during runtime.

Static testing examines software artefacts, such as requirements documents, design specifications, code files, and documentation. It can be performed manually or using automated tools specifically designed for static analysis.

Other testing subtypes

Black-box testing

In this approach, testers focus on the external behaviour of the software without considering its internal implementation details. Testers design test cases based on requirements, specifications, or user expectations. They evaluate the software's responses and compare them against the expected outputs.

White-box testing

This approach involves examining the internal structure and logic of the software. Testers can access the source code and design test cases based on code coverage criteria, such as statement coverage, branch coverage, or path coverage. They aim to uncover code implementation defects and thoroughly test all paths and conditions.

Grey-box testing

Grey-box testing combines elements of both black-box and white-box testing. Testers have partial knowledge of the software's internal structure or implementation details. They leverage this knowledge to design effective test cases while still considering the software's external behaviour.

Regression testing

Regression testing is performed when modifications or enhancements are made to the software. It ensures that the changes do not introduce new defects or break existing functionality. Testers rerun previously executed test cases to validate the software's behaviour and verify that it still performs as expected after the changes.

Final thoughts

The primary types of software testing can be classified as functional testing and non-functional testing. Manual and automated testing refer to the methods used, while static and dynamic testing, on the other hand, refer to different approaches to testing rather than types of testing. Software testing follows a hierarchy of:

Manual and Automated testing — Functional and Non-Functional Testing — Unit, Integration, System, Acceptance, Security, Performance, Usability, Compatibility testing — White box, Black-box, Grey-box, Regression, Smoke, Stress, Load, Incremental, etc.