Fire up your Start menu and take a look at the entries created. The installer at the time of this writing created the following entries.
Interactive Ruby - This is IRB in a standard command line window. Nothing more, nothing less.
RubyGems Documentation Server - This will run the gem server command for this version of Ruby. This starts a web server and provides access to your gem documentation for all installed gems. Note that this shortcut will appear to do nothing until you’ve actually installed at least one gem using the gem command. Once this server is running, you can point your browser to http://localhost:8808/.
Start Command Prompt with Ruby - If you didn’t add this version of Ruby to your path, you can start a command prompt with this version in the path here.
Documentation - Here is the Ruby API documentation in help file format, as well as a PDF copy of “The Book of Ruby.”