Ruby on Rails, is an open source web application framework for the Ruby programming language. It is intended to be used with an Agile development methodology that is used by web developers for rapid development.
Ruby on rails is often referred to as just “rails” or ROR. It was extracted by David Heinemeier Hansson from his work on Basecamp, a project management tool by 37signals. Ruby on Rails was originally introduced to the public in 2005 at version 1.0 and is now (in 2010) at version 3.0.