# SQL Database - Database is a collection of related data. - Data is: known facts that can be recorded and have implicit meaning. - Database is a collection of values in digital form, organized in a efficient way ## Data modeling Data model is a collection of concepts to describe the structure of a database. Structure of a database includes data types, relationships and constraints that apply to the data. - High Level: Conceptual data models - Low Level: Physical data models - Representational: implementational data models