What is a database? Definition, types and examples

A database is an organized collection of data stored in a computer system. It plays a vital role in handling mission-critical data for companies, including building applications, recording business transactions, managing customer data, and supporting business intelligence. There are two main types of databases: relational and non-relational. Relational databases use SQL to manage data and perform queries, while non-relational databases store data in a non-tabular format. The most popular database management systems include Oracle Database, MySQL, Microsoft SQL Server, PostgreSQL, and MongoDB.