Selenium 4, the latest version of the Selenium framework, introduces several enhancements over Selenium 3, including W3C standardization for WebDriver, a more advanced Selenium IDE, optimized Selenium Grid, and native support for Chrome DevTools Protocol. It offers new features like relative locators, TakeElementScreenshot API, and newWindow API, which contribute to a more stable and efficient testing process. The tutorial provides detailed guidance on upgrading from Selenium 3 to Selenium 4, particularly emphasizing Java bindings and tools like Maven and Gradle for managing dependencies. Although Selenium 4 is still in its Alpha stage, it is seen as a significant improvement over its predecessor, with the tutorial demonstrating how to execute tests on both local and cloud-based Selenium Grids, such as LambdaTest. The upgrade process involves fetching Selenium 4 from the Maven Repository and configuring project files accordingly, with similar steps applicable to other supported languages like Python, C#, PHP, Ruby, and JavaScript.