Interaction of the Selenium client library with the real browser is shown below.

Selenium WebDriver Architecture

Selenium WebDriver Architecture

Selenium client library is available in multiple programming languages including JAVA, C#, Python, Ruby, Javascript. Few more programming languages that are not maintained by Selenium can be found here.

These client libraries interact with the browser driver executables using JSON wire protocol over HTTP which passes the action and arguments to initiate user actions, which will be simulated on the real browsers.

That was just the introduction on how Selenium WebDriver works. In the next lesson, we will learn about the basics of an automation framework design.