From publisher blurb:
Each book in the Echelon Reference Series is written to be a complete reference for a single topic.
This book focuses on the barbarian class, savage warriors whose fury is legendary.
Barbarians are meant to be overwhelming, but this book can help.
In this book you will find 1 class, 19 archetypes, 64 class features, 108 class subfeatures (including 108 rage powers), and 19 feats, all accessible or directly related to the barbarian class. Also, 24 stat blocks for a mix of NPCs of levels 1-20, and monsters with levels in the barbarian class.
This book contains material from only the PRD.