Scott Young's book, "Ultralearning," The book explores Young's "ultralearning" methodology—a self-directed, intense approach to rapid skill acquisition. It details several case studies of individuals who mastered complex skills in remarkably short timeframes, highlighting nine core principles: metalearning, focus, directness, drill, retrieval, feedback, retention, intuition, and experimentation. These principles are illustrated through examples ranging from learning MIT's computer science curriculum to fluency in multiple languages. Finally, the book discusses applying ultralearning to accelerate, transition, or enhance careers.