What are the differences between 'Selenium-server-standalone.jar' and 'Selenium Client & WebDriver'?

Question

What are the Implementations differences between \'Selenium-server-standalone.jar\' and \'Selenium Client & WebDriver\'. Following is the link from SeleniumHQ.org websit

Answer 1

Selenium-server-standalone.jar is used for executing tests through Selenium Grid for distributing the test in multiple nodes and browsers.

Selenium Web Driver is used for executing in one machine in one browser at a time.