What is Bundler?
Bundler is a gem dependency manager for Ruby projects. It makes sure the correct gems and, perhaps more importantly, the correct gem versions are available to your program.
Getting Started with Bundler
One of the great things about Bundler is that it's so easy to use. You can be up and running in just minutes.
Deploying Applications with Bundler
Bundler can be use to "vendor" gems, allowing you to have a single and complete application directory that's ready to be deployed to multiple computers without having to run "bundle install" on each one.