I set up RVM and used it to install Ruby and a few other libraries. As I was going through various tutorials and set-ups of other technologies like Rails, I began getting confused about what I should do via RVM and what I should just do as the tutorials suggest.

One example is the RubyGems tutorial here: http://rubygems.org/pages/download

Should I download that tar file they are talking about? Seems unnecessary since that is what I thought RVM was for. Do I even need RubyGems? What is that for really?

Also, how do I actually get Rails? Is there a precise RVM command to actually download and install Rails?

ruby-on-rails ruby ruby-on-rails-3 rubygems rvm
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