Watir - 'Web Application Testing in Ruby', a free open-source family of web automation libraries in Ruby. The libraries support IE on Windows, Firefox on Windows, Mac and Linux, Safari on Mac, Chrome on Windows and Flash testing with Firefox. Note: Firewatir (targeting Firefox) is now merged with Watir. For a listing of additional tools that are available to extend some capabilities - see the Watir site and also Alternative Tools for Web Testing' page at the OpenQA site for more info.Here is some more info for the many other testing toolsHere is the comparison.
A late comment, if I may, mostly for other people landing on this page. Selenium by itself is good, but there is much more to a good test automation tool than automating the actions in the browser. Some examples are: reporting, parallelization, test data storage/access, data-driven testing and a ton of others. One might be better off leveraging a tool that provides a solid head start, like (disclamer: I'm a contributor), to avoid reinventing the wheel and to focus on the important stuff.–Aug 12 '18 at 18:06.