In these times of big data, machine learning, and cloud services, you cannot rely on having all of your data always in memory. Rather, you need to be able to effectively inspect and traverse the filesystem and manipulate its content at your leisure.
Examples of things you will be able to do after reading this chapter include configuring files in subdirectories with different naming variations, saving your data in efficient binary formats, reading protocols generated by other programs, and compressing your data in order to send it over the internet at fast speeds.