This API provides access to the Cyc Knowledge Base. OpenCyc is the open source version of the Cyc technology, a general knowledgebase and commonsense reasoning engine. OpenCyc includes the Cyc ontology, which contains hundreds of thousands of terms, plus millions of assertions relating the terms to each other, forming an upper ontology whose domain is all of human consensus reality. Using the API, a programmer can build an OpenCyc app with very little familiarity with CycL or with the OpenCyc KB. You might use the API to create apps that access the knowledge base for browsing, editing, or inference.