In many of the examples we have looked at so far, the data is little artificial since it has been generated using random numbers. It is now time to look at data held in files.

In this chapter, I'm going to concentrate on simple disk-based files, and reserve discussions of data stored in databases and on the Web for later chapters. Also, we will look at some of the statistical approaches in Julia that are incorporated both into the Julia base and into some of the growing number of packages covering statistics and related topics.