1. Chapter 1 Introduction

   1. Ruby's Elegance

   2. Ruby in Action

2. Chapter 2 Language Basics

   1. Command-Line Options

   2. Environment Variables

   3. Lexical Conventions

   4. Literals

   5. Variables

   6. Operators

   7. Methods

   8. Control Structures

   9. Object-Oriented Programming

   10. Security

3. Chapter 3 Built-in Library Reference

   1. Predefined Variables

   2. Predefined Global Constants

   3. Built-in Functions

   4. Built-in Library

4. Chapter 4 Standard Library Reference

   1. Standard Library

5. Chapter 5 Ruby Tools

   1. Standard Tools

   2. Additional Tools

   3. Ruby Application Archive

6. Chapter 6 Ruby Updates

   1. Summary of Changes

   2. Changes from 1.6.5 to 1.7.1

   3. The Future of Ruby

   4. Participate in Ruby

1. Colophon

Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects. The animal on the cover of Ruby in a Nutshell is a wild goat. Also known as a bezoar goat (Capra aegagrus), this species, found on the Greek islands and in Turkey, Iran, Turkmenia, and Pakistan, can grow to 300 pounds and up to 4 feet tall.

Goats have cloven hooves, which means they are split into two toes. Both males and females have short beards the same color as their wool and horns that curve backward. Bezoar goat horns are scimitar-shaped with sharp inside edges, and their bodies are covered in a coarse wool that can be black, brown, gray, red, or white. Their wool helps them survive harsh climates. Bezoar goats are herbivores, and their diet consists of grass, twigs, leaves, berries, and bark. Wild female and baby goats live together in packs of about 50; males live by themselves or in all-male packs. During the mating season, males give off an oily substance from their skin that attracts females. Males can get into terrific fights over females, and the winning male gets to mate. Females give birth to one or two babies, or kids.

Wild goats are listed as vulnerable in the 1996 IUCN Red List of Threatened Animals. An animal is listed as vulnerable when it isn't critically endangered but faces a high risk of extinction in the wild. Bezoar goats are losing more and more land to development in their native countries. Mary Anne Weeks Mayo was the production editor and proof reader, and Ellie Cutler was the copyeditor for Ruby in a Nutshell. Darren Kelly and Sheryl Avruch provided quality control. Derek DiMatteo provided production assistance. Lucie Haskins wrote the index.

Hanna Dyer designed the cover of this book, based on a series design by Edie Freedman. The cover image is a 19th-century engraving from the Dover Pictorial Archive. Emma Colby produced the cover layout with QuarkXPress 4.1 using Adobe's ITC Garamond font. Melanie Wang designed the interior layout based on a series design by Nancy Priest. Neil Walls converted the files from Microsoft Word to FrameMaker 5.5.6 using tools created by Mike Sierra. The text and heading fonts are ITC Garamond Light and Garamond Book. This colophon was compiled by Mary Anne Weeks Mayo

Whenever possible, our books use a durable and flexible lay-flat binding. If the page count exceeds this binding's limit, perfect binding is used.