Ruby on Rails is an application framework for web development. Specifically, it focuses on server-side functions and relies on the model-view-controller pattern. Rails is the framework itself, while Ruby is the programming language in which Rails is written. Ruby on Rails was designed to cut down on repetitive tasks and to be easy to learn with large, easily accessible libraries. It is open source as well, which means there is a large community that you can utilize to answer questions or improve your skills.