Ruby on Rail, often called RoR, or just Rails, is an open source web application framework for the Ruby programming language that closely follows the Model-View-Controller (MVC) architecture. It strives for simplicity and allowing real-world applications to be developed in less code than other frameworks and with a minimum of configuration. It is intended to be used with an Agile development methodology, which is often utilized by web developers for its suitability for short, client-driven projects.

RoR can do all that in a much easier, faster and cost effective way