Useful addition to the standard work by Matz

The book contains not even no introduction to Ruby itself a very tight together gathered, as in some other "cookbooks" the case and focuses entirely on the actual "recipes", a total of 341, which all in the steps of problem / solution / discussion . / For more information "are divided Where necessary because of the complexity, the code will be explained extremely detail; external resources are not entered for more information.

The first category relate to the standard data types and classes (strings, numbers, incl. Math functions, date and time, arrays, hashes, objects, modules and namespaces, you / File). The metaprogramming is treated.
Then to follow a whole lot of other issues: CSV, XML, PDF, TAR, ZIP and GZIP-processing, graphics with RMagick, Gruff and Sparklines, encryption, databases and other persistent data storage, also an extremely extensive (including XLS.) chapters on all kinds of network protocols and communication both as a client and as a server.

Also included is a more extensive chapter on Ruby on Rails with a very scarce and informative, but still re-ranging introduction and a few recipes, but which for the most part rather treat the general use Rails. Anyway, this book is not a substitute for an introduction as Learning Rails 3 or for the Rails Cookbook.

More advanced topics: Unit testing and documentation, Web Services and Distributed Programming, Creating Your Own Gems, harnessing Rake, threading and its pitfalls and solutions for creating command line tools in the style of classic Unix tools and GUI programming (Tk, wxRuby, Ruby / GTK, RubyCocoa), extension of Ruby (eg utilization of Java code under JRuby and writing and use of C extensions) as well as specifically for sysadmins, but also so interesting automation of all possible administrative tasks.

All in all a very useful aid for small everyday problems in programming with Ruby, but also a great book to broaden your horizons (Gems, Rake, Rails) and see what it 'out there' else so great for Ruby are.
A book that has definitely earned besides introducing books and / or standard work place as a reference on the shelf.