Re: HOWTO: Install Ruby on Rails on Ubuntu Linux
Step 6 is a horrible idea. The correct thing to do is to install the "ruby" package via apt-get. This ensures that /usr/bin/ruby points to the current Ruby installation in the future, without manually interfering with system directories.
How so? Installing Rails via the gem is the best way to do it. I think you misread that step. He didn't say install Ruby via a Gem, he said Rails.
RubyGems won't function without Ruby being installed.