In this chapter, we learned about some of the basic characteristics of data, common data issues, how to visualize data, and finally how to persist your work for reproducibility. As such, these topics are vast areas in and of themselves and this chapter should hopefully serve as an initial primer in these areas. In the next chapter, we will start exploring the field of machine learning using R. We'll learn about various algorithms in machine learning and the corresponding packages that provide easy access to a vast array of machine learning functionalities through R.