A knowledge graph, also known as a semantic network, represents a network of real-world entities—i.e. objects, events, situations, or concepts—and illustrates the relationship between them. This information is usually stored in a graph database and visualized as a graph structure, prompting the term knowledge “graph.”
The term ‘knowledge graph’ has been introduced by Google in 2012 to refer to its general-purpose knowledge base, though similar approaches have been around since the beginning of modern AI in areas such as knowledge representation, knowledge acquisition, natural language processing, ontology engineering and the semantic web. Today, KGs are used extensively in anything from search engines and chatbots to product recommenders and autonomous systems.