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.file extension RB - Ruby on Rails class file
File extension RB description:
Rails is a web-application framework that includes everything needed to create database-backed web applications according to the Model-View-Control pattern.
This pattern splits the view (also called the presentation) into "dumb" templates that are primarily responsible for inserting pre-built data in between HTML tags. The model contains the "smart" domain objects (such as Account, Product, Person, Post) that holds all the business logic and knows how to persist themselves to a database. The controller handles the incoming requests (such as Save New Account, Update Product, Show Post) by manipulating the model and directing data to the view.