When you have verified that the Web application looks as expected on all available browsers on your local machine, you can add additional execution servers to your testing environment to execute the tests for your Web application on multiple browsers in parallel.
To test your Web application on additional browsers, you have the following three options:
This option enables you to test a great variety of browsers without increasing the execution time of your test set and without requiring additional hardware. The additional cost is directly related to your testing effort, which means the frequency at which you are executing your test set and the size of your test set.
For information on running keyword-driven tests across multiple browsers, see Cross-Browser Testing with Keyword-Driven Tests