Neo4j is an open source, distributed data store used to model graph problems. It was released in 2007 and is sponsored by Neo4j, Inc., which also offers enterprise licensing and support for Neo4j. It departs from the traditional nomenclature of database technologies, in which entities are stored in schema-less, entity-like structures called nodes. Nodes are connected to other nodes via relationships or edges. Nodes can also be grouped together with optional structures called labels.
This relationship-centric approach to data modeling is known as the property graph model. Under the property graph model, both nodes and edges can have properties to store values. Neo4j embraces this approach. It is designed to ensure that nodes and edges are stored efficiently, and that nodes can share any number or type of relationships without sacrificing performance.[8]