Automation Testing vs. Manual Testing: What’s the Difference?

Software runs everything from our smartphones to spacecraft. With something as critical as software, thorough testing is essential to ensure it works correctly and doesn’t have bugs or errors that could cause problems. There are two main approaches to testing software — manual testing done by human testers and automation testing done by specialized software tools.

Which approach is better — manual or automated testing? The truth is, both have their strengths and ideal use cases. In this article, we’ll explore the automation vs manual testing differences to help you understand which approach, or a combination of both, is optimal for ensuring your software works reliably.

What Is Manual Testing?

Manual testing is when human testers check software by using it themselves. The testers go through the software’s screens, features, and workflows by clicking around and entering data, just like a real user would.

The testers follow step-by-step instructions called test cases. They input different combinations of information, navigate through the different screens, click on buttons and menus, and check that the results are what they should be. If anything doesn’t work right, the tester writes down the details in a bug report.

Manual testers also look at whether the user interface looks good and is easy to use. Their experience as a user helps them judge the overall quality of how the software looks, feels, and works.

The main benefit of manual testing is the human side. Testers can think critically to explore areas an automated test might miss. They can easily adapt if requirements change or new situations come up. Their real-world user view provides valuable feedback on usability.

When Should You Use Manual Testing?

While automated testing is fast for repeated test cases, there are several times when manual testing is still very useful:

• Exploratory testing. With no set testing scripts, exploratory testing relies on the skill of testers to mimic real-world usage and find hidden issues. The unplanned nature makes this style hard to automate.

• New software versions. When an application has major updates, it’s wise to begin with in-depth manual testing to understand new features before automating tests.

• Complex human interaction. Software involving human decision-making, emotions, or psychology can be difficult to automate well. Examples include chatbots, animated characters, voice interfaces, games, and more. Manual tests provide a more reliable human perspective.

• Small projects. For short projects with limited features, manually testing everything can be more cost-effective than writing automated test scripts.

So, while automation is incredibly useful for thorough, repeated testing of stable software, the human expertise and real-world user view of manual testing remain invaluable.

What Is Automation Testing?

Automation testing is using special computer programs to test other software programs automatically. Instead of human testers manually going through test steps, automated tests are pre-programmed instructions that can rapidly run tests on their own.

With automated testing, testers create scripts with instructions and test data for different situations. These scripts interact with the software the same way a user would — by simulating clicks, typing, data entry, and checking the expected results.

The scripts can run tests repeatedly, unattended, at high computer speeds. Automated testing tools can quickly test every possible combination of user inputs and actions, checking for any issues that may have been missed earlier. Automated tests provide consistent results by precisely following the programmed scripts. All test runs, and any defects found are fully recorded.

While manual testing automation needs technical skills, once automated scripts are built, they can be easily re-used. Tests can run simultaneously on multiple systems and browsers for thorough multi-platform testing.

The main benefits of automation testing are faster testing timelines, continual regression coverage, reduced manual effort, and improved accuracy over manual tests. This makes it ideal for rigorous testing of stable software versions.

When Should You Use Automation Testing?

Automated testing is very useful for situations like:

• Regression testing. As software gets updated, automated tests quickly verify no new bugs were introduced in existing functionality.
• Performance testing. Automated tools can thoroughly check performance by simulating millions of virtual users accessing the software.
• Cross-platform testing. With many operating systems, devices, browsers, etc., automated scripts standardize testing across this variety.
• Data testing. Tests requiring many different data inputs can be automated using data files.
• Cost savings. While initial setup has costs, once created, the automated scripts can be re-run endlessly, saving effort in the long-term.

And automated tests aren’t just coding — modern tools can also validate user interfaces, visuals, accessibility, and other usability aspects too.

Difference Between Automation Testing and Manual Testing

Now that we understand what manual testing and automated testing are, let’s look at the main differences between the two approaches side-by-side. While both help check software quality, they have some big differences in how the testing is done, their strengths and weaknesses, and when to use each one.

Test Coverage

Manual tests cover a set number of test scenarios based on documented instructions and what’s practical for humans to check. With limited time/people, many tests get skipped. Automated tests can theoretically test every single defined scenario by running complete test suites simultaneously on multiple systems. Complex variations and large data sets are easy for automation.

Exploratory vs Scripted

Manual testing allows open-ended, freestyle exploration of the software by thinking beyond documented test cases. Experienced testers can improvise new tests on-the-fly. Automated tests strictly follow pre-programmed instructions. Going outside of defined test scripts requires human intervention to create new automated tests.

Testing Documentation

For manual testing, detailed test cases and step-by-step instructions need to be created and maintained as documentation. This can be time-consuming but provides a clear blueprint for testers to follow.

With automated testing, the test scripts themselves effectively serve as the documentation. However, separate documentation is still needed for testing approaches, tool configuration, data mappings, etc.

Test Data Management

For manual tests, testers need to carefully setup and maintain test environments and data stores for testing different scenarios. This data management can be cumbersome.

Automated testing tools provide better capabilities to manage, provision, and bucket test data through techniques like data-driven testing, reading external data sources, and spinning up fresh test data on the fly.

Advantages of Automation Testing Over Manual Testing

In many cases, automated testing can provide big advantages over just manual testing. By using automation, you can get broader test coverage, faster feedback, greater accuracy and

cost savings.

First, automated tests are extremely fast and can rapidly run thousands of test cases in a small fraction of the time it would take human testers. Their computer speed allows running comprehensive test suites frequently, even for every new software version if needed.

Additionally, automated tests operate with total precision and consistency that humans cannot match. They will execute test steps exactly the same way, every single time. This eliminates human error risks, improves defect detection, and ensures repeatability.

Automated tools can also execute far more comprehensive testing than any realistic manual effort. Complex scenarios with many data inputs, configurations, and heavy loads are easy for automation. They can easily run millions of parallel tests against an application.

From a cost perspective, while automation requires upfront investment, it leads to major cost-savings over manual tests.

Advantages of Manual Testing Over Automation

While test automation is advanced, some application types still pose challenges to fully automate due to constraints like device interactions, browser compatibility, dynamic content, etc. Manual tests complement automation here.

The ideal approach leverages both manual and automated testing throughout the software lifecycle. Start with a solid manual testing foundation early, then implement robust automated regression packs as the product matures, while continuously using manual tests for subjective quality aspects.

Conclusion

When it comes to software testing, there is no one perfect solution. Both automation and manual testing are important for finding defects before users experience issues.

Automated tests are extremely fast, consistent, and can comprehensively test across huge numbers of scenarios, configurations, data sets, and heavy loads. However, as powerful as it is, it cannot replicate the creative, flexible testing of skilled human testers. The real-world user perspective and subjective evaluations of manual testing remain essential, especially early in development and for user-interactive systems.

At White Test Lab, our experts know how to combine smart automated testing with skilled manual testing for awesome software quality. We’ll partner closely with your team to create the perfect testing approach just for your needs. Reach out today to schedule a chat and see how our tailored testing solutions ensure exceptional quality for your applications.