From December 2012 to February 2013, I studied the book, The Science of Black Hair. A well written book by Audrey Davis-Sivasothy. If you want to understand your hair and how to better take care of it, this is the one of the best books to use.
I am very happy to say that Audrey has created a YouTube channel (ScienceOfBlackHair) that gives a visual representation of key information discussed in her book.
Here are some of the videos where talks about Moisture Basics.
Part 1: Moisture Basics: Moisturizing and Sealing Your Hair
Part 2: The Science of Black Hair: Hair and Hard Water
Part 3: The Science of Black Hair on pH Problems & pH Balancing (Moisture Basics 3/4)