Selenium RemoteWebDriver is a class that implements the WebDriver interface on a remote server, used to execute browser automation suites on a remote machine. It's distinct from Selenium WebDriver, which interacts with browsers directly using automation scripts. RemoteWebDriver acts as an interface to execute tests in a distributed environment, and it's primarily used for parallel testing across multiple operating systems and browsers. The Selenium Grid is a cloud-based platform that efficiently runs tests in distributed environments without manual configuration setup. It provides a quick turnaround and supports 3000+ browsers, operating systems, and devices. RemoteWebDriver can be implemented under the java.lang.Object and org.openqa.selenium.remote.RemoteWebDriver packages, with known subclasses including ChromeDriver, EdgeDriver, FirefoxDriver, InternetExplorerDriver, OperaDriver, and SafariDriver.