Ruby Version Manager (RVM) is a command-line tool which allows you to easily install, manage, and work with multiple ruby environments from interpreters to sets of gems.

Steps for Installation
Open terminal and run following commands.

• Step 1
  $ sudo apt-get install build-essential git-core curl
• Step 2
  RVM Installation
  $ curl -L get.rvm.io | bash -s stable
• Step 3
  $ echo ‘[[ -s “$HOME/.rvm/scripts/rvm” ]] && source “$HOME/.rvm/scripts/rvm”‘ >> ~/.bashrc
• Step 4
  $ ~/.bashrc
• Step 5
  $ . ~/.bashrc
• Step 6
  Check requirements for Ruby
  $ rvm requirements
• Step 7
  Install requirements of Ruby by RVM
  $ sudo apt-get install build-essential openssl libreadline6 libreadline6-dev curl git-core zlib1g zlib1g-dev libssl-dev libyaml-dev libsqlite3-dev sqlite3 libxml2-dev libxslt-dev autoconf libc6-dev ncurses-dev automake libtool bison subversion pkg-config
• Step 8
  Install Ruby with 1.9.3 version
  $ rvm install 1.9.3
• Step 9
  Check Rubygems version. Its installed with Ruby.
  $ gem -v
  1.8.24
• Step 9
  Install Rails latest version
  $ rvm gem install rails
• Step 10
  Check version of Ruby, Rails and Rubygems
  $ ruby -v
  ruby 1.9.3p194 (2012-04-20 revision 35410) [i686-linux]
  $ gem -v
  1.8.24
  $ rails -v
  Rails 3.2.8

Installation is complete. Now try RoR Apps.
If you find any error between steps then share it as comments.
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