Ruby on Rails is a web application framework that supports the development of web applications and is written in Ruby under the MIT license.
Ruby is an object-oriented, general-purpose programming language. Rails is a model view controller framework that provides default structures for a database, a web service, and web pages.
What can Ruby on Rails do?
Ruby on Rails covers both front and back end design and is at the heart of sites such as Twitter, while brands like Amazon and eBay also have Ruby on Rails projects.
One of the things that RoR can do is to handle all database communications, provide a template system for handling page sections and layouts, process Ajax updates and a plugins that are designed to make feature implementation easy.
RoR is most commonly used with the development of complex websites, particularly when the complex website involves a database.