what's the relationship between Selenium RC and WebDriver?

Question

I can see that since selenium 2.0, WebDriver and Selenium RC are packaged together for download. Now I primarily use WebDriver, but can I bring in Selenium RC in my testing scripts from now and then? Is there anything that Selenium RC is capable of but WebDriver is not, or vice versa?

Answer 1

You should probably start your research here (though you may have already gone over this): http://seleniumhq.org/docs/03_webdriver.html

I'll assume you're contrasting Selenium-RC to WebDriver, Selenium-IDE really isn't in the same ballpark.

Selenium uses JavaScript to automate web pages. This lets it interact very tightly with web content, and was one of the first automation tools to support Ajax and other heavily dynamic pages. However, this also means Selenium runs inside the JavaScript sandbox. This means you need to run the Selenium-RC server to get around the same-origin policy, which can sometimes cause issues with browser setup.

WebDriver on the other hand uses native automation from each language. While this means it takes longer to support new browsers/languages, it does offer a much closer 'feel' to the browser. If you're happy with WebDriver, stick with it, it's the future. There are limitations and bugs right now, but if they're not stopping you, go for it.

Selenium Benefits over WebDriver

• Supports many browsers and many languages, WebDriver needs native implementations for each new language/browser combo.
• Very mature and complete API
• Currently (Sept 2010) supports JavaScript alerts and confirms better

Benefits of WebDriver Compared to Selenium

• Native automation faster and a little less prone to error and browser configuration
• Does not require Selenium-RC Server to be running
• Access to headless HTMLUnit can allow tests to run very fast
• Great API