I think the claims made by the people hawking this book are some of the most disingenuous things I’ve ever read:

http://sourcemaking.com/design-patterns-simply

They are selling a rehash of the classic Gang of Four (GoF) Design Patterns book as a PDF, making preposterous claims which I’ll cut & paste here. You can’t make this stuff up.

The Whys:

Why should I read it?
When you finish reading this book, you can go to your boss and ask him for a promotion.

Why? Because using design patterns will allow you to get your tasks done twice faster, write bugless code and create an efficient and reliable software architecture.

How to become programming guru?
The main difference between a programming guru and a novice is the knowledge of secret coding tricks, as well as awareness of most cornerstones and the ability to avoid them.

Design patterns were created as a Bible of avoiding problems related to software design. Isn’t it a true guru’s handbook?

“Bugless code” after learning design patterns! I must be a poor learner, because I still have bugs in my code and I’ve lived with the GoF book for many years now. Unless you are writing code for the space shuttle, you’ve probably written your share of bugs, too. And bosses don’t give promotions because you read a book about patterns. Mine gave me promotions because of hard work, passion, and creativity in problem solving.

“Testimonials”
If you follow through to the order page, you see the publisher is based in the Ukraine. That explains the broken English “testimonials”:

Daniel Sommers, UK

I have learned all design patterns about a 3 days with this book. Thank you very much!!!!

and

Jeremy Parkinson, USA
Four month ago I was just coder in Boeing corp. I had a lot things to learn to get a level up in my skills, and I started with this book. Now I am a software architect and I happy, because nobody in my department is so good with programming as me!

I’d be pissed off if I were Boeing. That “testimonial” makes me think the talent there must be terrible. Boeing does “aerospace engineering.” Rocket scientists. Literally. I suspect they are a smarter bunch than “Jeremy Parkinson.”

Free Book Offer:

Buy our book now and get a free gift! (limited offer)
It is classic “Design Patterns” book by “Gang of Four”.

Amazon is selling the classic GoF book for $38, but this publisher is going to sell you a PDF for $20 and give you a $38 book for free. If they gave a single GoF book away for free, would that be considered a “limited offer”?

The odd thing is that the quality of the rest of the site appears, at first blush, quite good. The writing on the pages describing each of the patterns is good and without any outlandish claims. It makes me wonder if they didn’t get that copy from somewhere else. Regardless, the content on the site is sufficiently good that one wouldn’t need to buy their PDF.

Save your money. Or better yet, buy the real GoF book. It’s a classic for a reason, and there are products that nicely complement the book, like a wall poster detailing the original patterns in a striking visual way.