PostgreSQL is a powerful, open-source, object-relational database system known for its reliability, feature robustness, and performance. It's a popular choice for storing and managing data for various applications, from simple websites to complex enterprise systems. 

Here's a more detailed explanation:

Key Features and Concepts:

• Object-Relational Database:
  PostgreSQL combines the strengths of relational databases (like organizing data into tables with rows and columns) with object-oriented features (like custom data types and inheritance). 
• SQL Compatibility:
  It uses SQL (Structured Query Language) for querying and managing data, but it also extends SQL with its own features and functionalities. 
• ACID Properties:
  PostgreSQL ensures data integrity through ACID (Atomicity, Consistency, Isolation, Durability) properties, guaranteeing reliable transactions. 
• Extensibility:
  It allows users to define custom data types, functions, and operators, making it highly adaptable to different needs. 
• Open Source:
  Being open-source, PostgreSQL is freely available, has a large community, and can be modified and distributed without licensing costs. 
• Reliability and Scalability:
  It's known for its robustness and ability to handle large amounts of data and high traffic loads. 
• Geospatial Data Handling:
  PostgreSQL, with its PostGIS extension, is well-suited for applications involving geographic data. 
• Multi-Version Concurrency Control (MVCC):
  PostgreSQL uses MVCC, which allows multiple users to access the database concurrently without blocking each other, improving performance. 

In essence, PostgreSQL is a versatile and reliable database system that offers a wide range of features and is widely used in various applications due to its flexibility, scalability, and open-source nature. 

Sample Query

CREATE TABLE land_registry_price_paid_uk(
  transaction uuid,
  price numeric,
  transfer_date date,
  postcode text,
  property_type char(1),
  newly_built boolean,
  duration char(1),
  paon text,
  saon text,
  street text,
  locality text,
  city text,
  district text,
  county text,
  ppd_category_type char(1),
  record_status char(1));