I may be on questionable ground listing this as a "book", but it contains written information and has an ISBN. The pages are small and square, slightly smaller than a CD and about the weight of a baby's board book, hole punched in one corner, and held together by a large binder ring.

What I like:
The book is small enough and sufficiently durable to be tossed into a workout bag for easy reference at the health club. The binder ring may look silly, but it allows the book to lie flat when opened to any page.
Each yoga pose is illustrated by a cartoon of a lady with attitude, accompanied by a small animal companion. A pictogram in the upper right corner illustrates an easier version of the pose for beginners.
The back of each card contains the Sanskrit name of the pose, an English translation, tips for correct style, and suggestions for the benefits of that particular pose.
The poses are presented in groups, and each group is accompanied by 3 "mega benefit sequences", illustrating 6-8 poses that can be practiced in sequence to increase the overall effects.
A reference card at the back contains a pictogram index to the 48 poses; the back of this card contains the Sanskrit and English names for the poses.

What I don't like:
Egregious use of pink (my least favorite color) in the packaging (gauzy drawstring bag) and the illustrations.
The groups of poses are assigned arbitrary attributes, and each group is introduced with breezy advice from the author. I don't much care for this type of silliness, and yoga offers enough benefits that it doesn't need them. For those who like that sort of thing, the categories are:
* Sexy: fitness & confidence
* Calm: stress relief
* Energy: boost & invigorate
* Restore: feel like a kid again
* Cleanse: detox & purify
* Sanity: mood & balance
* Ragtime: PMS & period relief