What is PostgreSQL?

PostgreSQL is a powerful open-source object-relational database system that runs all the major operating systems such as Windows, Linux, Mac, and Solaris. It supports storage of binary large objects including images, sounds and video. It has interfaces for Java, Python, Perl, Ruby, C, C++, and other. 

Its features include:

• Multi-Version Concurrency Control (MVCC);
• tablespaces;
• query/planner optimizer;
• online backups;
• point in time recovery;
• case-sensitive; 
• formatting
• and many more.