Ruby on Rails is a web application framework written in Ruby. It is designed to make programming web applications easier by making assumptions about what every developer needs to get started. It allows you to write less code while accomplishing more than many other languages and frameworks.

Rails is opinionated software. It makes the assumption that there is a 'best' way to do things, and it's designed to encourage that way - and in some cases to discourage alternatives. If you learn 'The Rails Way' you'll probably discover a tremendous increase in productivity.