Ruby is a high-level, fully object-oriented programming (OOP) language. It is very powerful and relatively easy to learn, read, and maintain.
Sams Teach Yourself Ruby in 21 Days provides the best introduction to this language and addresses one of the key constraints it faces: "The paucity of quality English-language documentation is one of the few things holding Ruby back from widespread adoption," according to Dr. Curtis Clifton of Iowa State University¿s Department of Graduate Computer Science.
Day 1. Getting Started with Ruby.
Day 2. Hello, Objects!
Day 3. Containers.
Day 4. Iteration and Flow Control.
Day 5. The Characteristics of Objects.
Day 6. Ins and Outs.
Day 7. Catching Up on Details.
Day 8. Pattern Matching.
Day 9. Inheritance and Modules.
Day 10. Program File Layout, Program Design, and the General Case.
Day 11. Modules and Classes in More Depth.
Day 12. An Introduction to Recursion.
Day 13. Mastering the Operating System.
Day 14. Arguments, Blocks 'n Procs.
Day 15. Toward Habitable Interfaces.
Day 16. Putting It Together.
Day 17. Tk.
Day 18. Gtk.
Day 19. Some Advanced Topics (That Aren't So Hard).
Day 20. Working with the Web.
Day 21. Putting It Together.
Appendix A. irb Results from Day 1.
Appendix B. Installation Help.
Appendix C. The Debugger.
Appendix D. Essential Elements (Reserved Words, Standard Classes/Methods List).
Appendix E. Database Interaction.
Appendix F. Fox.