In this chapter, we explored a lot of material. We learned how the I/O system in Julia is constructed, how to work with files and DataFrames, and how to connect with databases using ODBC. The basics of network programming in Julia were also discussed, and then we got an overview of the parallel computing functionality, from primitive operations to map-reduce functions and distributed arrays.

In the next chapter, we will take a look at how Julia interacts with the command line and with other languages, and discuss a number of performance tips.