The RubyGems package comes as a tool useful for creating, sharing and installing these gems along with a server for hosting them.
If you want to write a Ruby application from scratch or modify an existing one, RubyGems is your first stop. RubyGems programmers can extend or change functionality in a Ruby application because of the reusability of standard code libraries (Gems) already created by fellow developers. Using simple commands on the RubyGems interface, they can pull in the gems and install your desired functionality for the end application.