Knowledge representation using logic is a formal approach to encoding information about the world in a structured and interpretable way. It employs logical systems, such as propositional logic and first-order logic, to represent facts, rules, and relationships between entities. Logic-based knowledge representation enables reasoning by applying inference rules to derive new facts from existing ones, ensuring consistency and transparency. This approach is widely used in artificial intelligence, expert systems, and automated reasoning, allowing machines to make informed decisions based on logical deductions.