The Ruby Version Manager is a command line tool to simply install and manage different versions of Ruby.

• rvm istall 2.3.1 for example installs Ruby version 2.3.1 on your machine.
• With rvm list you can see which versions are installed and which is actually set for use.

user@dev:~$ rvm list

rvm rubies

=* ruby-2.3.1 [ x86_64 ]

# => - current
# =* - current && default
#  * - default

• With rvm use 2.3.0 you can change between installed versions.