This chapter walks the reader through various structures of data. The main types of structures are structured, semi-structured, and unstructured data. We will also be applying modeling techniques to these types of datasets. In addition, readers will learn about various operations on the data model and various data model constraints. Moreover, the chapter gives a brief introduction to a unified approach to data modeling and data management. We will discuss the following topics:

• Identifying different data model structures, including structured and unstructured data
• Recognizing different data model operations, including selection, projection, union, and join
• Understanding different data model constraints and explaining why constraints are used to specify the semantics of the data 
• A unified approach to data modeling and data management