Active Support Core Extensions

This guide documents the Ruby core extensions defined in Active Support.

Rails Internationalization API

This guide covers how to add internationalization to your applications. Your application will be able to translate content to different languages, change pluralization rules, use correct date formats for each country and so on.

Action Mailer Basics

This guide describes how to use Action Mailer to send and receive emails.

Testing Rails Applications

This is a rather comprehensive guide to doing both unit and functional tests in Rails. It covers everything from 'What is a test?' to the testing APIs. Enjoy.

Securing Rails Applications

This guide describes common security problems in web applications and how to avoid them with Rails.

Debugging Rails Applications

This guide describes how to debug Rails applications. It covers the different ways of achieving this and how to understand what is happening "behind the scenes" of your code.

Configuring Rails Applications

This guide covers the basic configuration settings for a Rails application.

Rails Command Line Tools and Rake Tasks

This guide covers the command line tools and rake tasks provided by Rails.

Caching with Rails

Various caching techniques provided by Rails.

Asset Pipeline

This guide documents the asset pipeline.

Working with JavaScript in Rails

This guide covers the built-in Ajax/JavaScript functionality of Rails.

Getting Started with Engines

This guide explains how to write a mountable engine.

The Rails Initialization Process

This guide explains the internals of the Rails initialization process as of Rails 4