Manual Testing vs Automation Testing in Software Testing

In the previous tutorial, we discussed both Manual and Automation Testing separately. On the one hand, Manual testing is a type of software testing which allows the manual execution of tests with the help of humans. On the other hand, Automation testing is another type of software testing where the test execution is done using automation tools and test scripts.

Let us study the comparison between both manual and automation testing. Before moving forward, let us recall what manual and automation testing is.

Manual Testing

Manual testing is a type of software testing where all the activities are performed manually with the help of humans. In manual testing, all activities such as test case creation, test execution, defect reporting, and more are done manually without using any automation tool. It is the classical approach of testing the software where testers analyze and examine all the requirements given by the client before proceeding to the actual testing. Testing is executed from the perspective of the client's needs which are defined in the requirement specification document.

The objective of using manual testing is to deliver a product that is defect free and working as per the client or customer’s specifications. The tested software should meet the quality standard of the client’s expectations. To create a high-quality product, we use manual testing, which helps in identifying all the hidden defects in the system by testing all the functional and non-functional requirements. If the testing team finds any flaws, they will assign them to the development team for a fix. Once the defect is fixed, it will be returned to the testing team for re-testing. After the completion of testing with no open defects, we can deliver the product to the production team or client.

Type of Manual testing

Manual testing is further categorized into three different categories, as mentioned below:

1. White Box testing
2. Black Box testing
3. Grey Box testing

White Box testing

It is one of the manual testing types which focuses on the testing of code and the internal structure of the application. In white box testing, each line of code is tested by developers to identify bugs and defects in it. Once the white box testing is completed, the application is handed over to QA (testing team). It is also called Glass box testing or transparent testing due to the visibility of code.

Black Box testing

Another type of manual testing is Black box testing. It focuses on the application's behaviour and functionality and verifies whether it works according to the client's expectations. It is opposite to white box testing as there is no visibility of code and internal structure. It is usually performed by testers.

Grey Box testing

Another type of manual testing is Grey box or Gray box testing, which is a combination of both white box and black box testing. In grey box testing, we have partial visibility of the source code and internal structure of the software. Therefore, it is performed by a person who knows both programming language and testing.

Automation Testing

Automation testing is another type of software testing where the test execution is done with the help of automation tools and test scripts. In other words, automation testing is implemented on any system with the help of specific automation tools without any human interruption. It is a software testing process performed using various automation testing tools. The primary focus of automation testing is on substituting the physical human testing efforts with the system and automation tools.

The primary purpose of using automation testing is that it helps in controlling the test execution flow as per the written test scripts, inserting the test data into AUT (application under test), handling the test execution, comparing the test results (actual vs expected), and generating the test execution reports. Using automation testing, we can automate other testing activities that can’t be done manually.

Like Manual testing, it is also performed to identify all possible bugs and issues of the system and delivers a 100% defect-free product. With the help of automation testing, we can efficiently perform the required repetitive tasks and activities to perform testing. Automation testing is done only after the completion of manual testing.

Types of Automation Testing

Like manual testing, automation testing is also divided into different categories. There are mainly two types of automation testing, which are mentioned below:

1. Functional Testing
2. Non-Functional Testing

Functional Testing

Functional testing is a software testing technique used to test the applicable requirements or specifications of the software defined by the clients. In other words, functional testing validates the functionality of the software by testing all its small components of it. The objective of functional testing is to thoroughly examine and test that every piece or feature of the software should work per the pre-defined requirements. We can do functional testing with manual testing as well as automation testing. Functional testing is further categorized into several types of testing, such as Unit testing, Smoke testing, Sanity testing, Integration testing, etc.

Non-Functional Testing

Non-functional testing is a software testing process which focuses on the non-functional aspects of the application under test (AUT). It works in the opposite direction of functional testing. Functional testing validates what software does, whereas non-functional testing validates how the software works. It contains all other modules which are not covered in the functional tests. It comprises all the non-functional requirements such as performance, security, usability, reliability, compatibility, etc., therefore, also known as quality requirements. Non-functional tests are difficult to perform manually. Consequently, we use automated test cases to perform non-functional tests.

Difference between Manual Testing and Automation Testing

Below are the key differences between manual testing and automation testing:

Parameters of testing	Manual Testing	Automation Testing
Definition	A type of software testing where test execution is done manually by the testing team.	A type of software testing where test execution is performed with the help of automation tools.
Reliability	Manual testing is less reliable as there are chances of human errors such as missing bugs and faults in the system. Hence, it is less reliable.	Automation testing is more reliable than manual testing as it is done with the bits of help of automation tools and scripts. Hence, the changes of errors are less, and it is more reliable.
Processing time	The processing time of manual testing is high compared to automation testing, as testers perform each task manually. Hence, it is a time-consuming process.	Automation testing is much faster than manual testing as there is less human intervention.
Initial Investment	The initial investment of manual testing is less than automation testing, and the ROI will get low for the long-term experience.	The initial investment in automation testing is high as it requires a massive amount of investing in tools, and the ROI will be better in the long run.
Investment	Investment is only required for human resources needed for testing.	Investment is required for automation tools and equipment and skilled automation resources.
User-friendliness	Manual testing provides a user-friendly experience and also validates the user-friendliness of the application.	Automation testing does not provide the guaranteed user-friendliness of the application.
Setup	Manual testing requires a simple setup for test execution.	Automation testing requires a little less complicated setup for test execution.
Exploratory Testing	Exploratory testing is easily possible via manual testing.	Automation testing doesn’t give the liberty of such random testing.
Test Coverage	In manual testing, achieving 100% test coverage is very difficult.	In automation testing, it is easy to achieve sufficient test coverage compared to manual testing.
Programming Knowledge	Manual testing doesn’t require any programming knowledge to perform testing activities.	Automation testing requires a good knowledge of programming languages as we can’t prepare test scripts without having programming knowledge.
Framework	Manual testing doesn’t use frameworks for testing. However, it uses specific checklists and processes to draft test cases.	Automation testing uses different frameworks such as data-driven framework, keyword-driven framework, hybrid framework, modular framework, and linear framework for faster testing.
Reusability	Reusability in manual testing is a bit complicated as it could be possible only when test cases need to be executed once or twice.	Reusability of test scripts is very common in automation testing. We can easily reuse the test scripts for multiple test cases.
Performance Testing	Performance testing cannot be possible through manual testing.	With the help of automation testing, we can easily do all types of performance testing of the application.
Build Verification Testing	Building verification testing (BVT) via manual testing is complicated and time-consuming.	We can perform build verification testing (BVT) efficiently with the help of automation testing.
Batch Execution Testing	It is not possible to do batch execution with manual testing.	Batch execution testing is only possible with automation testing, as all written test scripts can be executed simultaneously.
Test Report	In manual testing, we usually create test reports in excel, where test results are available readily.	In automation testing, all users (developers, testers, and clients) can quickly log in to the testing tools and keep track of all the test reports and records.
Platform Independent	Manual testing is platform-dependent.	Automation testing is completely platform-independent as it can be done anywhere and anytime with the environment setup.