Ruby is an object-oriented, interpreted programming language. It is object-oriented in that it views (and interacts with) everything as an object. Ruby is interpreted in that its programs are compiled and executed by an interpreter at runtime. Th is allows you to make changes to your Ruby programs and then immediately run the programs to see how they work, without having to go through the extensive compilation that is required by many other programming languages.

Ruby is a cross-platform programming language, which means that its programs can run on Windows, Mac OS X, UNIX, Linux, and many other operating systems. Th is allows you to leverage your Ruby programming skills, maximizing the investment you’ve made in learning Ruby. You can even apply your Ruby programming skills to the development of web applications, using a specialized Ruby framework known as Ruby on Rails.

Ruby is easy to learn, yet quite powerful. Th is makes it an excellent choice for fi rst-time programmers. It is a great programming language for tackling all kinds of small tasks. At the same time, Ruby is powerful enough to support the development of the most complicated programming tasks, making it a great language for experienced programmers looking for an advanced object-oriented programming language.

Best of all, Ruby is free. If your computer is running on a UNIX or Linux operating system, Ruby may already be installed. If not, you can download and install it directly from the Internet. Free installation packages are available for Microsoft Windows users as well. Th is book is dedicated to teaching you what you need to know to begin programming with Ruby. By the time you have fi nished this book, you will have developed a good understanding of the fundamentals of Ruby programming and will have a solid foundation to build upon in becoming an eff ective Ruby programmer.