I was disappointed when I read this book. As a cosmetology student, we were required to study this book but I found that there were so many errors and inaccuracies in it that you stopped believing what you were reading after a while and you began to question everything. A college level book, or even a high school level book for that matter,would never be accepted to be used for teaching if it contained the kinds of errors in this book, and I am talking about the book in general (not a specific version/year). Poorly written.