Check out example codes for "rvm install new ruby version". It will help you in understanding the concepts better.

Code Example 1

$ ruby -v 						# Check ruby version 
$ rvm install ruby-X.X.X        # Install specific ruby version
$ rvm list						# List ruby versions
$ rvm use ruby-X.X.X			# Choose a version to use
$ rvm use ruby-X.X.X --default  # Set a version as default

Code Example 2

\curl -sSL https://get.rvm.io | bash

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