Stare decisis is a legal principle that means "to stand by things decided." It requires courts to follow the precedents set by previous decisions in similar cases. This ensures consistency and predictability in the law, allowing individuals and entities to understand their rights and obligations. When a court makes a ruling, that decision becomes a precedent for future cases. Lower courts are generally bound to follow the rulings of higher courts within the same jurisdiction. This system helps maintain stability in the legal framework and promotes fairness in judicial proceedings.