Ruby on Rails, often referred to as Rails, is a powerful web application framework written in the Ruby programming language. It allows developers to build robust and high-performing applications quickly by emphasizing convention over configuration. This means that Rails comes with a set of sensible defaults, enabling beginners to focus on writing their code rather than getting caught up in setup and configuration details. If you're just starting out, the Rails community is incredibly supportive, providing extensive documentation and numerous online resources to help new developers get up to speed.

One of the key features that makes Ruby on Rails so appealing to beginners is its adherence to the MVC pattern (Model-View-Controller). This architecture separates application logic into three interconnected components, which helps in organizing code efficiently. For example, the Model handles the data and business logic, the View takes care of the user interface, and the Controller manages the communication between the Model and View. By understanding this pattern, newcomers can create well-structured applications and enhance their coding skills significantly as they explore the magic of Ruby on Rails.

As a Ruby developer, staying updated with the latest tools and libraries is essential for enhancing productivity and code quality. Here are the top 10 gems every Ruby developer should know:

1. Rails: The most popular framework for web applications, it provides a robust structure for building a variety of projects.
2. Devise: A flexible authentication solution, it simplifies user management and enables rapid development of authentication features.
3. Pry: This advanced Ruby shell enhances debugging capabilities with powerful introspection and navigation features.

In addition to those essentials, consider these gems to further enhance your Ruby projects:

1. RSpec: The go-to testing tool for Ruby, it promotes behavior-driven development and ensures code reliability.
2. ActiveRecord: A powerful Object-Relational Mapping system, it bridges the gap between database and Ruby objects, making data manipulation seamless.
3. Sidekiq: An efficient job processing library, it allows developers to handle asynchronous tasks in a scalable manner.

Building a RESTful API with Ruby on Rails can be a straightforward process if you follow a few essential steps. First, ensure you have Ruby on Rails installed on your system. You can create a new Rails application by running the command rails new my_api --api in your terminal. This command initializes a new Rails app configured specifically for APIs, setting up a lightweight stack. Once the application is created, navigate to the app directory with cd my_api and generate your first resource. Use the command rails generate scaffold Post title:string body:text to create a simple resource that includes a title and body for your posts.

After generating your resource, run rails db:migrate to prepare your database. Your next step involves configuring the routes for your API. Open config/routes.rb and modify it to include your resource by adding resources :posts. This will provide you with all the necessary CRUD endpoints. Finally, start your server with rails server and test your API endpoints using a tool like Postman or curl. By following these steps, you'll have a fully functional RESTful API built with Ruby on Rails, ready for further development and integration.