There are a bunch of command line utilities that comes with ruby and rails,
You can find them via your ruby/rail installation's bin folder, e.g. on a windows machine, your bin folders, could be something similar to:
C:\RailsInstaller\Ruby2.1.0\bin
Here are the main utilities you'll find in this folder:
- bundle
- bundler
- gem
- irb
- rails
- rake