How to Win Friends and Influence People by Dale Carnegie is a classic self-help and interpersonal-communication book focused on improving relationships, communication, leadership, and social confidence. First published in 1936, the book presents practical principles for understanding people and building stronger relationships in both personal and professional life. Carnegie emphasizes showing genuine interest in others, listening carefully, avoiding unnecessary criticism, remembering names, giving sincere appreciation, and approaching disagreements with empathy rather than hostility. The book also explains how to gain cooperation, influence people without creating resentment, handle criticism and conflict, and encourage others to improve. Its central idea is that effective influence comes less from forcing people to accept your viewpoint and more from understanding their needs, respecting their perspective, and making them feel valued.