A graph database, also called a graph-oriented database, is a type of NoSQL database
that uses graph theory to store, map, and query relationships. A graph database is
essentially a collection of nodes and edges. Each node represents an entity (such as a person
or a business) and each edge represents a connection or relationship between two nodes. In
a graphical visualization, the edges are the lines that connect any two nodes. Every node in
a graph database is defined by a unique identifier, a set of outgoing edges and/or incoming
edges, and a set of properties expressed as key/value pairs. Each edge is also defined by a
unique identifier, a starting-place (node), and an ending-place (node), together with a set
of properties. This essentially means that if one can draw a diagram of the data on a
blackboard, then one can also store that data in a graph database. pdf 
31:15 – Business and Planetary Boundaries Graph
Business and Planetary Boundaries Graph – 31:15