This chapter covered foundational concepts of how Tableau works with data. Although you will not usually be concerned with what queries Tableau generates to query underlying data engines, having a solid foundational understanding of Tableau's paradigm will greatly aid you as you analyze data. Having a basic understanding of connecting to various data sources, working with extracts, customizing metadata, and the difference between joins and blends will be key as you begin deeper analysis and more advanced visualizations such as those covered in the next chapter.