Selenium is one of the most powerful open source browser automation tool available in the market to the date. Selenium is not a single tool but a suite of tools which actually evolved with time.
The Selenium tool suite comprises of
1. Selenium IDE : A Firefox Plug-in to record and play tests (Other platforms are not supported as of now)
2. Selenium Remote Control : Allows exporting of test suites across different OS/platforms
3. Selenium Grid: Allows control to many Selenium Machines.
