Install RVM (Ruby Version manager) in Ubuntu 14.04
Ruby Version Manager (RVM) is a tool that managers Ruby application environments and enables switching between them. This is more of a personal note, as I always end up re-searching about this.
Install via PPA
Add RVM PPA.
sudo apt-add-repository ppa:rael-gc/rvm
sudo apt-get update
Install RVM, Ruby
sudo apt-get install rvm
Restart your terminal, or logout/login.
rvm install ruby