You must install gem selenium-webdriver first:
gem install selenium-webdriver
Then you can run the ruby program:
#You need to require the gem "selenium-driver" require "selenium-webdriver"
You can find additional information:
about webdriver and ruby (all of the above was an attempt to generalize it)
About Ruby API
As you can see right away, the Webdriver API itself has a different “style” of regular selenium ruby programs ... If you want to use the webdriver and still continue to program using the Selenium-API, you should probably Chechen Selenium2.0 Remote Server , since it seems that he will use Webdriver in a transparent way, while maintaining the same famous Selenium ruby Api
If I am mistaken in some part of the information, please correct me and we will clarify everything together :)
PD: The best relationship information found between Selenium and Webdriver was this blog post
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