FAQs, Help, and Tutorials

Thirty-seven Reasons I Love Ruby - By Hal Fulton.
http://rubyhacker.com/ruby37.html

Ruby Tips - Provides coding tips for the language's users.
http://www.rubytips.org

Phrogz - By David Thomas and Andrew Hunt. Offers a beginner guide to start with the language.
http://phrogz.net/ProgrammingRuby/

RubyLearning.com - Set of thorough study notes, and class, for those new to Ruby and meeding a solid introduction to its concepts and constructs. By Satish Talim.
http://rubylearning.com/

A Practical Introduction to Ruby: First Steps - Beginners introduction, on installing Ruby, and writing a first simple script.
http://coolnamehere.com/geekery/ruby/rubytut/part01.html

Ruby FAQ - Questions and official answers on Ruby.
http://www.rubycentral.com/faq/

Ruby Programming - IBM developerWorks group space: articles, podcasts, RSS feeds, courses.
http://www.ibm.com/developerworks/spaces/ruby

Ruby Slides - Provides an introduction to the language with slides. [English, Russian, French]
http://www.approximity.com/ruby/

RubyCocoa Resources - Documentation and examples, as digital books, for RubyCocoa, a bridge between Ruby and Objective-C, a way to make desktop programs with Ruby.
http://www.rubycocoa.com/

Ruby User's Guide - Original Japanese version by matz. First English translation by GOTO Kentaro and Julian Fondren. Further translation and editing by Mark Slagell.
http://www.rubyist.net/~slagell/ruby/

Learning Ruby - By Daniel Carrera. Introduces programming, Ruby, assumes familiarity with computers in Unix X Terminal environment, but not Ruby; simple descriptions, many screenshots. Unfinished, but well done and useful for what is done.
http://www.math.umd.edu/~dcarrera/ruby/0.3/

Ruby Embedded into C++ - Describes how to embed Ruby interpreter in C++, gives skeleton to build on, treats concepts of embedding, advanced topics like SWIG. Descriptions, code, diagrams, links, news.
http://metaeditor.sourceforge.net/embed/

Ruby-Doc.org - Ruby documentation project: links and downloads of programming information, on many aspects of Ruby.
http://www.ruby-doc.org/

Try Ruby - Beginner's basic tutorial, online, interactive, works in Web browser, has Ruby interpreter above with lessons below.
http://tryruby.hobix.com/

Meshplex : Ruby Tutorial - Provides a Ruby and Rails guide for beginners.
http://www.meshplex.org/wiki/Ruby/