Selenium is a suite of tools to automate web browsers across many platforms.
At the core of Selenium is WebDriver, it's a code interface and implementation to manipulate and perform automation actions in browsers.
The ide permits to create browser automation script from a GUI and
See also: https://intuit.github.io/karate/
To run tests on a grid of machines and manage multiple environments from a central point, making it easy to run the tests against a vast combination of browsers/OS