패키징 시스템. Perl의 CPAN 비슷한 넘.

gems list
gems query --remote
gems install rails --include-dependencies

• http://docs.rubygems.org/
  RubyGems Manuals
• http://rubyforge.org/
  루비 패키지들
• RubyGems
  A comprehensive guide to finding, creating and using Ruby resources called gems.

• see also Ruby