Data modeling is a critical step in developing any information system, as it defines the structure of data and its relationships. A data model can be divided into three levels: conceptual, logical, and physical. The conceptual level defines what the system contains, while the logical level defines how the database management system should be implemented. The physical level describes how to implement the information system using a specific technology. Data modeling is used in various methodologies, including relational modeling and dimensional modeling, which focus on different aspects of data storage and analysis. These methodologies differ in their approach to handling time series data, with relational modeling focusing on temporal validity and dimensional modeling considering time as an analytical dimension. Understanding these concepts is essential for effective data modeling and developing a well-structured information system.