Design Patterns; Elements of Reusable Object-Oriented Software. Gamma, Helm, Johnson, Vlissides. 1995. ISBN 0-201-63361-2.
Published by Addison-Wesley http://www.aw-bc.com/catalog/academic/product/0,1144,0201633612,00.html —- Also known as GOF or The Gang of Four.
Patterns home page: http://hillside.net/
A brief introduction to Design Patterns is contained in this editorial introduction to the Special Issue on Patterns and Pattern Languages in the October 1996 issue of Communications of the ACM Software Patterns [http://www.cs.wustl.edu/~schmidt/CACM-editorial.html]
Framework overview: [http://www.cs.wustl.edu/~schmidt/CACM-frameworks.html]
Design Pattern Tutorials [http://www.cs.wustl.edu/~schmidt/tutorials-patterns.html]
Is this book up to date enough that it would help the reader write different types of object oriented programs specifically using Objective-C and Cocoa?
Absolutely. This book is well-written and a good foundation. Most recent books on the topic just add to it, and refer to it constantly. Specifically, if you’re writing object-oriented programs, you need to read this book. – MichaelMcCracken
Additionally I am quite sure the authors looked toward ObjectiveC and NeXTStep when they wrote the book. Remember that in 2009, Cocoa is 20+ years old. Cocoa is the evolution of NeXTstep which shipped commercially in 1988.
Moreover the book uses examples written in SmallTalk (as well as C++), which is very close to ObjC.
There is a Cocoa specific design patterns book: http://www.amazon.com/Cocoa-Design-Patterns-Developers-Library/dp/0321535022 http://my.safaribooksonline.com/9780321591210