PostgreSQL is a free, open-source relational database that began as the POSTGRES project at UC Berkeley in 1986.
No single company owns it. The PostgreSQL Global Development Group holds the copyright and a core team governs the project.
PostgreSQL is the official name and Postgres is an accepted alias.
A fresh PostgreSQL 18.1 install we inspected had 3,413 functions, 70 base data types and 62 bundled extensions.