Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. This is the perfect guide for everyone, especially those who are interested in learning about Actinic Keratosis which is a premalignant condition of thick, scaly, or crusty patches of skin. Read about classification, prevention, diagnosis, treatment and more. This book will provide you in-depth information about the disease and guide you on how to treat it. Project Webster represents a new publishing paradigm, allowing disparate content sources to be curated into cohesive, relevant, and informative books. To date, this content has been curated from Wikipedia articles and images under Creative Commons licensing, although as Project Webster continues to increase in scope and dimension, more licensed and public domain content is being added. We believe books such as this represent a new and exciting lexicon in the sharing of human knowledge.