A data scientist needs to learn statistics, machine learning, and other new methods and technologies, and this book briefly sketch them but does not try to teach them in any detail. However, data scientists need to understand the fundamental concepts of information organization, resource description, category design, and classification that are at the heart of this book. Data scientists need to select resources wisely and decide how best to describe them, they need to understand that resource description and categorization can be biased, they need to understand tradeoffs and complements between people and computers, and they need to understand when interpretability of features and organizing principles are more important than a bit more classification accuracy in a machine learning model.