Daniel Kahneman's Thinking, Fast and Slow synthesizes decades of research that revolutionized our understanding of human judgment and decision-making. Kahneman, a psychologist who won the Nobel Prize in Economics, describes two systems of thought: System 1, which operates automatically and quickly, and System 2, which allocates attention to effortful mental activities. The book catalogs the cognitive biases that arise from System 1's shortcuts: anchoring effects, availability heuristics, overconfidence, and many others. Kahneman's research, much of it conducted with Amos Tversky, showed that humans systematically deviate from rational choice theory in predictable ways. The implications extend from personal finance to public policy, from medical diagnosis to legal judgment. Kahneman writes accessibly about technical research, using examples and exercises that allow readers to experience the biases he describes. He is honest about the limits of debiasing, noting that even experts who know about biases fall prey to them. Thinking, Fast and Slow has influenced fields from economics to medicine to artificial intelligence. It is one of those rare books that genuinely changes how readers see themselves and the world. Essential reading for anyone interested in psychology, decision-making, or the question of how to think more clearly.