As per the Selenium’s founders, Selenium automates browsers. That’s it! And what you do with that power is entirely up to you. Today Selenium is one of the most widely used UI Automation tool. You can download the latest stable versions of Selenium JAR files from selenium jars download. Programmers from any of the background like java, python, perl, php, .net and C# etc, can start their Selenium career right away. Compared to the other tools, Selenium support the use of framework. Framework reduce the time to code and time to test. Implementation of DevOps is spreading like wildfire and Selenium is an integral part of DevOps lifecycle. Selenium can be easily integrated with numerous open source tools like maven, JUnit, TestNG, Jenkins and sikuli. Selenium can execute multiple test cases at the same time (parallel testing). There is an increase in demand for Selenium Tester, among all the tools available in the market, Selenium has the greatest demand.