One of the main frameworks we use here at our Coding Bootcamp is Ruby on Rails. Here is a explanation of what Ruby on Rails is.
Rails is a development tool which gives developers a framework. It provides structure for all the code that you will write. The Rails framework helps developers build websites and applications, because it abstracts and simplifies common repetitive tasks.
Rails is written in Ruby, and is used to speed up development of web applications and coding applications and the appeal of Ruby to developers lies in the elegance and terseness of the language.
Another characteristic of Rails is the emphasis on RESTful application design. REST (Representational State Transfer) is a style of software architecture based around the client-server relationship. It encourages a logical structure within applications, which means they can easily be exposed as an API (Application Programming Interface).
Ruby code is very readable and mostly self-documenting. This increases productivity, as there is less need to write out separate documentation, making it easier for other developers to pick up existing projects.
Rails has developed a strong focus on testing, and has good testing libraries such as Rspec which is very popular for doing TDD (Test Driven Development).