The first part of this chapter will cover key aspects of data structure, including types such as structured, unstructured, semi-structured, and metadata. This chapter will also discuss data types, such as categorical, ordinal, numerical, and binary data, and explain the differences between numeric, integer, Boolean, and string data. Additionally, measurement and rating scales, including the Likert Scale, Semantic Differential Scale, Numerical Rating Scale, and Visual Analog Scale, will be introduced. Finally, this chapter explores the characteristics and challenges of big data, providing a comprehensive overview for all readers. The second part will explain how to start a new project, introduce the types of data that R can handle, show where to find reliable datasets, guide us in creating or importing our owned data, and review how to assess data quality.