Selenium is a free (open source) automated testing suite for web applications across different browsers and platforms. It is quite similar to HP Quick Test Pro (QTP now UFT) only that Selenium focuses on automating web-based applications. Testing done using Selenium tool is usually referred as Selenium Testing.
Selenium is not just a single tool but a suite of software's, each catering to different testing needs of an organization. It has four components.
When we talk about automation testing, Selenium always finds its way to the conversation. Being one of the best tools for automation testing, Selenium is well loved by developers and testers across the globe. But the question that remains is that there are many automation testing tools available in the market that delivers almost the same results.
Selenium is basically used to automate the testing across various web browsers. It supports various browsers like Chrome, Mozilla, Firefox, Safari, and IE, and you can very easily automate browser testing across these browsers using Selenium WebDriver.
One of the many things that adds to the advantages of Selenium is its open source availability. So, being an open source tool, Selenium is a publicly accessible automation framework and is free, with no upfront costs. So, you can save bucks here and use them for other good causes.
“One Selenium script for all browsers” is what Selenium community have been working on and improvising every day. As per StatCounter, Chrome, Firefox, Safari, Internet Explorer, Opera, and Edge browsers are the most used browsers worldwide and Selenium script is compatible with all the mentioned browsers. You don’t need to rewrite scripts for every browser, just one script for all browsers.
Different people use different operating systems and it is necessary that your automation tool supports all of them. Selenium is yet a highly portable tool that supports and can work across different operating systems like Windows, Linux, Mac OS, UNIX, etc.