Ruby language is one of the most elegant computer languages out there. You can write highly efficient code with Ruby. It is also very popular and bagged the programming language of the year award in 2006! In this post, I will look at the free ebooks available for Ruby.

1. Programming Ruby, The Pragmatic Programmer’s Guide - This is one of the best free ebooks available for Ruby. The first edition of this book is available online. A copy of this book is also included in the Ruby language download. I would suggest this as the first book for learning Ruby.

2. Mr. Neighborly’s Humble Little Ruby Book - This is a short treatise on the Ruby language, covering language basics and some library functions. PDF version of this ebook (144 pages) can be downloaded after registering at the site.

3. Why’s (Poignant) Guide to Ruby - This is an interesting Ruby book and is available online. This e-book covers Ruby in deep, but not everyone may like the novel type style used. It is also the funniest book I have read so far. You can also download a PDF version here.

4. The Little Book of Ruby - Supposed to be the “fastest and the easiest way to learn Ruby by example”, this book is available as a PDF download. You can also download sample code used in the book. Data structures are explained in detail.

5. Learning Ruby - This book is still in development and covers the basics. You can read the book online or download a zipped version.

6. Ruby user’s guide - The ultimate reference to the Ruby language and covers the language in depth. This can be read online.

7. Ruby Quick Reference - This is a single page quick reference guide to Ruby. This is an ideal reference to keep beside your desk.

8. A little ruby, a lot of objects - This is a Ruby book under construction. The chapters are available as PDF. This book covers the language from the object oriented viewpoint.

9. Data Structures and Algorithms with Object-Oriented Design Patterns in Ruby - This is a book on data structures and algorithms. The language used for examples is Ruby. Use this book once you have learned the basics of Ruby language. You can read this book online.