There aren't many Ruby books as of September 2001. With the exception of Programming Ruby, all of the following titles have yet to be published as of the writing of this book. We trust there will be more soon.
• Programming Ruby, Dave Thomas and Andy Hunt. Addison-Wesley, 2000.The first Ruby book in English, sometimes known as the "Pickaxe Book" because it has a pickaxe and some ruby gems on the cover. At the time of this writing, this is the "bible" for Ruby programmers, and it will continue to be used in the future for its excellent tutorial value and reference value.
• Ruby in a Nutshell, Yukihiro Matsumoto. O'Reilly and Associates, 2001. A Ruby book from Matz himselfa translation of the Japanese Ruby Pocket Reference; sure to be a valuable resource.
• The Ruby Programming Language, Yukihiro Matsumoto. Addison-Wesley Professional, 2002.Another book from the creator of Ruby. This is slated to be more than twice the length of Ruby Essentials, giving room for more examples and discussion.
• Teach Yourself Ruby in 21 Days, Mark Slagell. SAMS Publishing, 2001.This book is targeted for beginners who want to pick up Ruby quickly.
• The Ruby Developer's Guide, Michael Neumann. Syngress Media, Inc., 2001.The author is known to be a significant contributor to the Ruby community.