OpenCyc

OpenCyc is a large, open-source knowledge base and reasoning engine that contains a vast amount of general knowledge about the world. It was developed from the Cyc project, which aims to enable computers to understand and reason about everyday concepts, much like humans do. OpenCyc includes facts, relationships, and rules about various subjects, making it useful for artificial intelligence applications. It helps computers interpret information, answer questions, and make inferences by providing a structured way to connect ideas and knowledge in a way that machines can process.