RubyGems
RubyGems, the Ruby package manager, should be installed on your machine if you previously have installed Ruby. Verify this by running:
$ which gem
Update RubyGems
To update to its latest version with:
$ gem update --system
Install gems
To install a gem (Ruby package), run:
$ gem install <gemname>
To install without generating the documentation for each gem (faster):
$ gem install <gemname> --no-document
List installed gems
$ gem list
To check if any installed gems are outdated:
$ gem outdated
Update installed gems
To update all gems or a particular gem:
$ gem update [<gemname>]
Remove old gem versions
RubyGems keeps old versions of gems, so feel free to do some cleaning after updating:
$ gem cleanup