introduction to nosql can also be stored as single entitythis lowers the cognitive burden of working with the data for those used to seeing articles all the time examples of document stores are mongodb and couchdb graph databases the last big nosql database type is the most complex onegeared toward storing relations between entities in an efficient manner when the data is highly interconnectedsuch as for social networksscientific paper citationsor capital asset clustersgraph databases are the answer graph or network data has two main componentsnode --the entities themselves in social network this could be people edge --the relationship between two entities this relationship is represented by line and has its own properties an edge can have directionfor exampleif the arrow indicates who is whose boss graphs can become incredibly complex given enough relation and entity types figure already shows that complexity with only limited number of entities graph databases like neo also claim to uphold acidwhereas document stores and keyvalue stores adhere to base webshop customer of knows delphine thewiseone freddy stark knows likes customer of archery octopus table owner of fritz von braun likes friend of friend of jos the boss figure graph data example with four entity types (personhobbycompanyand furnitureand their relations without extra edge or node information the possibilities are endlessand because the world is becoming increasingly interconnectedgraph databases are likely to win terrain over the other typesincluding the still-dominant relational database ranking of the most popular databases and how they're progressing can be found at