Practical Ruby Gems is a comprehensive guide to utilizing and creating Ruby Gemsready-made Ruby code modules that can be easily added to the projects of Ruby and Rails. This book is ideal for Ruby programmers and web developers who use Rails and wish to extend the functionality of their projects. You will get first choice of 34 of the best and most useful gems, which form the core of this book. Youll learn how Ruby Gems can be used for Credit card validation. And much, much more! Youll also learn how to package and distribute your own Ruby Gems. And this book takes a detailed look at how different gems between the operating system, then you'll be prepared whether your desktop runs OS X, Windows, or Linux. Youll also learn how you can share code more easily between projects, optionally share your contributions with the world!