Ubuntu is the official OS for this course. These are the suggested ways that you can run Ubuntu:
Verify if Ruby is already installed in your system. At the terminal type:
ruby -v
If the output is “ruby 2.3.0” or better you’re good to go, so you can skip the following instructions. Otherwise, install Ruby 2.3. At the terminal type:
sudo add-apt-repository ppa:brightbox/ruby-ng
sudo apt-get update
sudo apt-get install ruby2.3 ruby2.3-dev