Automation Testing Vs Manual Testing

software testing is a process, to evaluate the functionality of a software application with an intent to find whether the developed software met the specified requirements or not and to identify the defects to ensure that the product is defect-free in order to produce a quality product


Check this ANSI/IEEE 1059 Standard Definition of Software Testing.


Software Testing is an integral part of any project.




It is categorized into two areas namely Manual Testing & Automation Testing. Both manual testing and automation testing have their own advantages and disadvantages but it’s worth knowing the difference between manual & automation testing and when to you use manual testing and when to use automated testing.


First, we will see what is Manual testing & Automation Testing.


What is Manual Testing?
Manual testing is the process of testing the software manually to find the defects. Tester should have the perspective of an end-user and to ensure all the features are working as mentioned in the requirement document. In this process, testers execute the test cases and generate the reports manually without using any automation tools.




Types of Manual Testing:
Black Box Testing
White Box Testing
Unit Testing
System Testing
Integration Testing
Acceptance Testing
Black Box Testing:?
Black Box Testing is a software testing method in which testers evaluate the functionality of the software under test without looking at the internal code structure. This can be applied to every level of software testing such as Unit, Integration, System and Acceptance Testing.


White Box Testing:
White Box Testing is also called Glass Box, Clear Box, and Structural Testing. It is based on application’s internal code structure. In white-box testing, an internal perspective of the system, as well as programming skills, are used to design test cases. This testing usually done at the unit level.


Unit Testing:
Unit Testing is also called as Module Testing or Component Testing. It is done to check whether the individual unit or module of the source code is working properly. It is done by the developers in developer’s environment.




System Testing:
Testing the fully integrated application to evaluate the systems compliance with its specified requirements is called System Testing AKA End to End testing. Verifying the completed system to ensure that the application works as intended or not.


Integration Testing:?
Integration Testing is the process of testing the interface between the two software units. Integration testing is done by three ways. Big Bang Approach, Top Down Approach, Bottom-Up Approach


Acceptance Testing:?
It is also known as pre-production testing.? This is done by the end users along with the testers to validate the functionality of the application. After successful acceptance testing. Formal testing conducted to determine whether an application is developed as per the requirement. It allows customer to accept or reject the application. Types of acceptance testing are Alpha, Beta & Gamma.




There are many types of software testing but here we dealt mainly about Manual and Automation Testing. Here you could read the complete list of software testing types.


When to use Manual Testing?
Exploratory Testing:
Exploratory testing will be carried out by domain experts. They perform testing just by exploring the functionalities of the application without having the knowledge of the requirements.


Usability Testing:
To verify whether the application is user-friendly or not and was comfortably used by an end-user or not. The main focus in this testing is to check whether the end-user can understand and operate the application easily or not. An application should be self-exploratory and must not require training to operate it.


Ad-hoc Testing:
Ad-hoc testing is quite opposite to formal testing. It is an informal testing type. In Adhoc testing, testers randomly test the application without following any documents and test design techniques. This testing is primarily performed if the knowledge of testers in the application under test is very high. Testers randomly test the application without any test cases or any business requirement document.


When do you prefer Manual Testing over Automation Testing?
We prefer Manual Testing over Automation Testing in the following scenarios


When the project is in the initial development stage.
When testing user interfaces especially their visual aspects.
If the project is a short term and writing scripts will be time-consuming when compared to manual testing
When exploratory or Adhoc testing needs to be performed.
If the test case is not automatable. Example captcha.
Manual Testing Pros and Cons
Advantages of Manual Testing:
Manual testing can be done on all kinds of applications
It is preferable for short life cycle products
Newly designed test cases should be executed manually
Application must be tested manually before it is automated
It is preferred in the projects where the requirements change frequently and for the products where the GUI changes constantly
It is cheaper in terms of initial investment compared to Automation testing
Requires less time and expense to begin productive manual testing
It allows tester to perform adhoc testing
There is no necessity to the tester to have knowledge on Automation Tools
Disadvantages of Manual Testing:
Manual Testing is time-consuming mainly while doing regression testing.
Manual testing is less reliable compared to automation testing because it is conducted by humans. So there will always be prone to errors and mistakes.
Expensive over automation testing in the long run
It is not possible to reuse because this process can’t be recorded






What is Automation Testing?
Automation testing is the process of testing the software using an automation tools to find the defects. In this process, executing the test scripts and generating the results are performed automatically by automation tools. Some most popular tools to do automation testing are HP QTP/UFT, Selenium WebDriver, etc.,


Some of the popular automation testing tools


HP QTP(Quick Test Professional)/UFT(Unified Functional Testing)
Selenium
LoadRunner
IBM Rational Functional Tester
SilkTest
TestComplete
WinRunner
WATIR
When to use Automation Testing?
We do Automation testing in the following areas:


Regression Testing:?
Repeated testing of an already tested program, after modification, to discover any defects introduced or uncovered as a result of the changes in the software being tested or in another related or unrelated software components. So, regression testing is best suitable for automated testing because of frequent code changes and it is beyond the human capacity to execute tests in a timely manner.


Read more about regression testing here


Load Testing:??
It is to verify that the system/application can handle the expected number of transactions and to verify the system/application behavior under both normal and peak load conditions. Automated testing is also the best way to complete the testing efficiently when it comes to load testing. It is best suited for automation testing.




Read more about load testing here


Performance Testing:
This type of testing determines or validates the speed, scalability, and/or stability characteristics of the system or application under test. Performance is concerned with achieving response times, throughput, and resource-utilization levels that meet the performance objectives for the project or product. It is best suited for automation testing.




Read more about performance testing here


The tests which can be done through automated or manual approach:


Integration Testing:
Integration Testing is the process of testing the interface between the two software units. Integration testing is done by multiple approaches such as Big Bang Approach, Top-Down Approach, Bottom-Up Approach, and Hybrid Integration approach.


Check this detailed Integration Testing Complete Guide




System Testing:
Testing the fully integrated application to evaluate the system’s compliance with its specified requirements is called System Testing AKA End to End testing. Verifying the completed system to ensure that the application works as intended or not.


Unit Testing:
Unit Testing is also called Module Testing or Component Testing. It is done to check whether the individual unit or module of the source code is working properly. It is done by the developers in the developer’s environment.


Acceptance Testing:
It is also known as pre-production testing.? This is done by the end-users along with the testers to validate the functionality of the application. After successful acceptance testing. Formal testing conducted to determine whether an application is developed as per the requirement. It allows the customer to accept or reject the application. Types of acceptance testing are Alpha, Beta & Gamma.


In interviews, you may be asked to answer the following question


Which tests cannot be automated?
Let’s see which tests cannot be automated. Test which take too much effort to automate are


Exploratory Testing
User interface testing
Adhoc Testing
When do you prefer Automation Testing over Manual Testing?
We prefer Manual Testing over Automation Testing in the following scenarios




To handle repetitive and time-consuming tasks
When there is a need of parallel testing
To do non-functional testing like load, performance, stress testing
To avoid human errors
Automated Testing Pros and Cons
Advantages of automated testing:
Automation testing is faster in execution
It is cheaper compared to manual testing in the long run
Automated testing is more reliable
Automated testing is more powerful and versatile
It is mostly used for regression testing
It is reusable because the automation process can be recorded
Does not require human intervention. Test scripts can be run unattended
It helps to increase the test coverage
Disadvantages of Automated Testing:
It is recommended only for stable products
Automation testing is expensive initially
Most of the automation tools are expensive
It has some limitations such as handling captcha, getting visual aspects of UI such as fonts, color, sizes etc.,
Huge maintenance in case of repeated changes in the requirements
Not all the tools support all kinds of testing. Such as windows, web, mobility, performance/load testing.