Can you explain what is meant by command line when using TestNG?

The command line when using TestNG is a way to run tests from the terminal or console using the java command and specifying TestNG parameters. Usually, you invoke TestNG by passing it a test configuration XML file or test classes directly.

Example of running from the command line:

java -cp "path/to/testng.jar;path/to/your/tests" org.testng.TestNG testng.xml

Here, -cp sets the classpath, org.testng.TestNG is the main class for launching, and testng.xml is the file describing the tests. This method is convenient for integration with CI/CD, automation, and running tests without an IDE.