Ruby on Rails (or "Rails") is an open-source web application development framework written in the Ruby programming language. It's one of the most popular Ruby libraries and one of the top reasons developers choose to learn Ruby.

Modern web applications can be very complex with many layers. Rails makes web development easier, providing a pre-built structure for development and everything you need to build a web app.

What is Ruby on Rails used for?

A framework simplifies the creation of web applications. It does this by providing default structures for your code, any databases you use, and the web pages the application will serve.

You can think of a framework almost like Legos. With a framework, you get pre-built "Legos" of code that you can mix, match, and modify to build a custom web application, which means you don't have to create everything from scratch.

Ruby on Rails uses the Model-View-Controller (MVC) architectural pattern used by many other web frameworks — one of the most well-known patterns in development. The MVC pattern separates a web application's code into three interconnected parts:

The Model, which holds the data structure of the application.

The View, which represents the visual part of the web app as web page templates.

The Controller, which connects the data to the View and contains the business logic of the application.

This pattern makes Rails very flexible and useful for all types of web applications.

Rails has been used for many types of web apps. You can use it to build complete web applications that span both the front end and the back end.

The Model and Controller would be considered the back-end part of the application. The View handles the front end by generating the actual web page that people see in the browser, along with included JavaScript and HTML. You can also use Rails to create web services or APIs that return JSON for use by other applications.

What are the advantages and disadvantages of Ruby on Rails?

The biggest advantage to Rails is that it makes web development quick and easy. This means a small team of developers can create a web app and deploy it quickly.

The Ruby programming language ecosystem also provides libraries that can extend the Rails framework with even more pre-built features. It's been a top choice of frameworks for many startups because of these reasons.

Ruby on Rails is one of the best choices of frameworks if:

You need to handle complex business logic

You need to find developers to build an application readily and quickly

You have a limited budget

You want to deliver a web app quickly