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Software Testing Methodologies: All You Need To Know

Written by Hy Nguyen | Feb 12, 2025 8:27:07 AM

Software testing methodologies have evolved over time. In this article, we'll go through the most common methodologies that QA teams around the world follow

Agile vs Waterfall Methodology

1. Waterfall Methodology

The Waterfall model is a linear and sequential software development approach, where progress flows downward like a waterfall through distinct, predefined phases. Testing is treated as a separate phase that occurs after development is complete.

Phases of the Waterfall Model:

  1. Requirement Gathering – All project requirements are collected upfront.
  2. System Design – A complete blueprint of the system is created based on requirements.
  3. Implementation (Development) – Developers code the software according to the design.
  4. Testing – Once the software is fully developed, testers check for bugs and issues.
  5. Deployment & Maintenance – The final product is deployed, and any post-launch issues are addressed.

Testing in Waterfall:

  • Testing only begins after development is completed, making it difficult to catch issues early.
  • Defects found in later stages are costly to fix because they often require major rework.
  • Waterfall follows a structured approach, making it suitable for well-defined projects with clear requirements that are unlikely to change.

2. Agile Methodology

The Agile model is an iterative and incremental approach that emphasizes continuous feedback, flexibility, and customer collaboration. Testing is an integral part of the entire development cycle, rather than a final phase.

Phases of Agile Development:

  1. Concept & Planning – The team identifies high-level features and prioritizes them.
  2. Iteration Development – Work is broken into short cycles (sprints), typically 2-4 weeks.
  3. Continuous TestingAgile testing happens simultaneously with development to catch issues early.
  4. Feedback & Refinement – The product is reviewed, improved, and adjusted after each iteration.
  5. Final Deployment & Maintenance – The product is continuously improved even after release.

Testing in Agile:

  • Testing happens continuously throughout development instead of being a final step.
  • Testers work closely with developers, ensuring early bug detection and rapid fixes.
  • Agile methodologies like Scrum and Kanban emphasize automation, TDD (Test-Driven Development), and continuous integration to maintain software quality.

Read More: Agile vs Waterfall Methodology

Software Testing Models

For different software testing methodologies, there are corresponding models.

1. V-model

In the past, QA teams had to wait until the final development stage to start testing. Test quality was usually poor, and developers could not troubleshoot in time for product release. 

The V-model solves that problem by engaging testers in every phase of development. Each development phase is assigned a corresponding testing phase. This model works well with the nearly obsolete Waterfall testing method.

On one side, there is “Verification”. On the other side, there is “Validation”.

  • Verification is about “Are we building the product right?”
  • Validation is about “Are we building the right product?”

2. Test Pyramid model

As technology advances, the Waterfall model gradually gives way to the widely used Agile testing. Consequently, the V-model also evolved to the Test Pyramid model, which visually represents a 3-part testing strategy.

 

Most of the tests are unit tests, aiming to validate only the individual components. Next, testers group those components and test them as a unified entity to see how they interact. Automation testing can be leveraged at these stages for optimal efficiency.

Read More: Test Pyramid: A Guide To Implement in Practice

3. The Honeycomb Model

The Honeycomb model is a modern approach to software testing in which Integration testing is a primary focus, while Unit Testing (Implementation Details) and UI Testing (Integrated) receive less attention. This software testing model reflects an API-focused system architecture as organizations move towards cloud infrastructure.

Functional Testing vs Non-functional Testing

Software testing can also be broken down into functional testing vs non-functional testing.

1. Functional Testing

Functional testing focuses on verifying what the system does by testing specific functionalities against defined requirements. It ensures that the application behaves as expected and meets business needs.

Key characteristics:

✔ Tests features and user interactions with the software.
✔ Ensures correct input-output behavior based on requirements.
✔ Black-box testing approach – the tester doesn’t need to know the internal code structure.

Types of Functional Testing:

  1. Unit Testing – Testing individual components or functions of the software.
  2. Integration Testing – Ensuring multiple components work together.
  3. System Testing – Testing the entire system as a whole.
  4. User Acceptance Testing (UAT) – Final validation by end-users before release.
  5. Regression Testing – Rechecking existing functionalities after changes or updates.
  6. Sanity & Smoke Testing – Quick tests to check if major functionalities work before deeper testing.

2. Non-functional Testing

Non-functional testing focuses on how the system performs rather than what it does. It evaluates performance, security, usability, and scalability to ensure a smooth user experience.

Key characteristics:

✔ Tests the quality and behavior of the software under different conditions.
✔ Helps identify bottlenecks, vulnerabilities, and UX issues.
✔ Requires specialized tools (e.g., JMeter for performance, OWASP ZAP for security).

Types of Non-functional Testing:

  1. Performance Testing – Evaluates system speed, responsiveness, and stability.
    • Load Testing – Measures performance under expected user load.
    • Stress Testing – Determines system behavior under extreme conditions.
    • Scalability Testing – Tests how well the system grows with increased load.
  2. Security Testing – Identifies vulnerabilities, exploits, and data protection flaws.
  3. Usability Testing – Ensures ease of use, intuitive navigation, and user satisfaction.
  4. Compatibility Testing – Verifies software behavior across devices, browsers, OS versions.
  5. Reliability & Maintainability Testing – Checks system stability and ease of maintenance.

Manual Testing vs Automation Testing

Software testing can also be classified by its approach: whether testers choose to do it manually with the help of automation technologies.

  • Manual testing is the approach where a human tester directly interact with the system like an end user to find bugs.
  • Automation testing is a testing approach that involves using specialized tools and software to execute predefined test cases automatically without human intervention.

Thanks to automation testing, testers don’t have to manually interact with the system over and over, which is a time-consuming process. All they have to do is click the “Run” button, sit back, and let the script do the work.

Software Testing With Katalon



Katalon accompanies your QA team throughout the entire software testing life cycle.

With Katalon, you can write tests in 3 modes (no-code, low-code, full-code), manage tests in a centralized dashboard, schedule test runs, execute tests across environments, and generate detailed reports.

And all of that can be done for web testing, API testing, and mobile application testing. In other words, Katalon is a centralized platform for all of your testing activities.

Feature highlights:

  • Suitable for any testing needs, from individual testers, QA teams, to large enterprises
  • No-code, low-code, and full-code scripting in Groovy
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  • Run tests across local machine, cloud, on-premise environments, with easy CI/CD integrations
  • AI-powered regression testing with TrueTest
  • Data-driven testing and BDD testing supported
  • Diverse integration ecosystem with ALM and CI/CD tools
  • Detailed reports with analytics, screenshots, videos, HTML Snapshot, and Test Suite report email
  • Detailed technical documentation and video tutorials on Katalon Academy

Website: Katalon
Price: Free and flexible paid plans

 

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