Ruby on Rails is a web application framework that is designed to make programming web applications easier and more enjoyable. It includes features like an object-relational mapper called Active Record that allows database rows to be represented as objects, conventions that reduce configuration, and support for test-driven development. Rails is built on Ruby, an interpreted object-oriented programming language, and aims to be programmer friendly and allow powerful applications to be built quickly. Several experts praise Rails for lowering the barriers to entry for programming and being a well-thought-out framework.