Introduction to RubyInstaller
The RubyInstaller project provides a self-contained Windows-based installer that includes a Ruby-language execution environment and a baseline set of required RubyGems and extensions, integrated with a MSYS2 installation.
To install Ruby, in the Download section choose the version you would like, and click the .exe link (under the name of the version) to download the installer. Use Windows Explorer to navigate to where you saved the .exe file and double-click it to run the installer.
The Ruby Installer is currently available only for Windows platforms.