Database

An organized collection of structured information, or data, typically stored electronically in a computer system.

A database is an organized collection of data stored and accessed electronically. Databases are managed by database management systems (DBMS) that provide mechanisms for defining, creating, querying, updating, and administering data. The two primary categories are relational databases (such as PostgreSQL, MySQL, and SQL Server) and non-relational databases (such as MongoDB, DynamoDB, and Redis).

Relational databases organize data into tables with defined schemas and use SQL for queries. Non-relational (NoSQL) databases offer more flexible data models including document, key-value, column-family, and graph structures. The choice depends on the application's data access patterns, consistency requirements, and scalability needs.

APIs commonly serve as the interface layer between clients and databases. Rather than exposing database queries directly, APIs provide controlled access through defined endpoints. An API gateway adds security and governance by authenticating requests and enforcing rate limits before they reach the database-backed service, protecting against unauthorized access and query overload.