1. Concept

Test Automation is the use of software or tools to automate the software testing process. It involves creating automated test scenarios and using automated tools to execute those scenarios, instead of doing manual testing, the test scripts are designed and programmed by experience in software testing. These scenarios can be designed to test the software's features, performance, security, reliability, and other requirements. Test Automation helps to speed up testing, reduce errors and ensure the integrity of the software testing process. It also saves time and cost for the software development company. However, Test Automation also has limitations and cannot completely replace manual testing

2. Advantages and disadvantages of Automation Testing

a. Advantages of Automation Testing
1. Save time and costs: Test Automation can automate the testing process, which saves time and costs compared to performing tests manually.
2. Increase accuracy and reliability: Test Automation eliminates the shortcomings of manual testing that can be caused during testing, helping to increase the accuracy and reliability of testing.
3. Increase repeatability and increase test coverage: Test Automation can execute test scenarios repeatedly and can test a wider range than manual testing.
4. Increase test speed and performance: Test Automation can execute test scenarios more quickly and efficiently than manual testing.
5. Increased error detection: Test Automation can find errors more accurately and quickly than manual testing.      

b. Disadvantages of Automation Testing
1. High technical requirements: Test Automation requires highly specialized knowledge of engineering and technology, programming and logical thinking, and different programming languages.
2. Difficulty in creating and maintaining test scenarios: Creating and maintaining test automation scripts is a complex job and requires care and perseverance.
3. Cannot comprehensively test: Test Automation cannot comprehensively test and guarantee the stability of the software

3. How Automation Testing works

Automation Testing is an automated software testing method that uses software and automated testing tools to execute test scenarios without human intervention. How Automation Test works usually includes the following steps:
1. Selection of Automation Test tool: First, choose an Automation Test tool suitable for the project. There are different types of Test Automation tools, including free and commercial tools, such as Selenium, Appium, Katalon Studio, Ranorex, and a few others.
2. Build test scenarios: After choosing the Automation Test tool, the next is to build test scenarios. These test scripts are programmed using one of today's popular programming languages ​​like Java, Javascript, Python, or C#.
3. Setting up the test environment: During the test scenario building, the test environment must be set up to execute the test. The test environment includes web browsers, operating systems, applications, and other supporting tools.
4. Test Scenario Execution: After having built the test scenarios and set up the test environment, we can execute these test scenarios. Test scripts are executed automatically, without human intervention.
5. Analysis of test results: After executing test scenarios, test results are saved and analyzed. The detected bugs and issues will be recorded in the test report.
6. Bug Fixing: Finally, the bugs and problems discovered during testing will be corrected and the test scenarios re-executed to ensure that the software works properly and efficiently.

4. To become Automation Testing, where to start:

1. Learn the basics of Testing: To understand test automation, you need to have knowledge of Testing. You should learn about testing techniques, software testing, unit testing, integration testing, acceptance testing, system testing, performance testing, security testing, processes, standards, and general knowledge about Testing.
2. Learn a programming language: Automation Testing is usually done using programming languages ​​and tools like Java, Python, Ruby, C#, etc. You need to learn a programming language to be able to understand test automation scenarios and create test automation scripts.
3. Learn test automation tools: Automation tools help you to create and execute test automation scenarios. There are many popular tools like Selenium, Appium, Katalon Studio, Robot Framework, and many more. You need to learn and master these tools to be able to use them effectively.
4. Practice and create test automation scenarios: After you have basic knowledge of Testing, programming languages ​​, and test automation tools, you should practice by creating scenarios. automated testing. This will help you better understand how to execute test automation and create effective test automation scenarios.
5. Learn more about related technologies and techniques: Testing is a vast field and is always updated with new technologies and new techniques. You should continue to learn and improve your knowledge of related technologies and techniques so that you can apply them to test automation.
If you want to dive deeper into the field of automation testing and become an expert in the field, you can learn more about related certifications like ISTQB Foundation Level or Selenium WebDriver Certification.
Also, you can search online courses and materials to learn more about Automation Testing. Related forums and communities are also great places to network and share knowledge with other experts in the field.