gem --help

gem --help
RubyGems is a sophisticated package manager for Ruby.  This is a
basic help message containing pointers to more information.

 Usage:
   gem -h/--help
   gem -v/--version
   gem command [arguments...] [options...]

 Examples:
   gem install rake
   gem list --local
   gem build package.gemspec
   gem help install

 Further help:
   gem help commands            list all 'gem' commands
   gem help examples            show some examples of usage
   gem help gem_dependencies    gem dependencies file guide
   gem help platforms           gem platforms guide
   gem help <COMMAND>           show help on COMMAND
                                  (e.g. 'gem help install')
   gem server                   present a web page at
                                http://localhost:8808/
                                with info about installed gems
 Further information:
   http://guides.rubygems.org

See also

• RubyGems, gem, gemfile, .gemspecs, gem install, gem environment, gem --help