In the previous chapter you have seen how to acquire data from data sources such as databases or files. Once you have the data in DataFrame format, they are ready to be manipulated. The manipulation of the data has the purpose of preparing the data so that they can be more easily subjected to analysis. In fact, their manipulation will depend a lot on purposes of those who must carry out the analysis, and it will be performed for making more explicit the information you are looking for. Especially in preparation for the next phase, the data must be ready to the data visualization that will follow in the next chapter.