PostgreSQL is an open-source database, which is rather object-relational. So there are relations between two or more tables. The database stores lots of information and it should be structured. That’s why you break this information into tables.
It is used as a primary data store by startups and large enterprises alike. This way, they support internet-scale applications, solutions, and products characterized as internet-scale.
Using Foreign Data Wrappers and JSON it is possible to link with other data stores and be a federated hub for polyglot database systems.
PostGIS extension makes the database a geospatial data store for location-based services and geographic information systems (GIS).
The database runs dynamic websites and applications as an alternative to the LAPP stack – Linux, Apache, PostgreSQL, and PHP, Python, and Perl.
You can learn more about PostgreSQL here.