We recommend Ruby 2.1 or newer for use with Rails. Rails requires Ruby 1.9.3 or newer.
We recommend managing your Ruby installation through rbenv. It’s an easy way to run multiple versions for different applications and update when a new release is made.
With Ruby installed, you can install all of Rails and its dependencies through RubyGems on the command line:
gem install rails
New versions of Rails can be installed the same way.
Make your application
Create your application skeleton and start the server:
rails new path/to/your/new/application
You’re running Ruby on Rails! Follow the instructions on http://localhost:3000.