It's worth mentioning that although the result is slightly different than the file created in Excel, Excel can read this one just as easily (you do have to tell Excel that the fields are comma separated). And the earlier code can read the file exactly the same way.
In addition to CSV files, you can also create and read files with fixed length fields and records. This is an old technique that you will find still in use. (Back in Cobol and Fortran days, almost all files had fixed length fields and records.)
Chapter 12 seems to be just a grab-bag of topics loosely connected by the topic "text". I started programming with IBM Extended Character Set (better known as EBCDIC - pronounced "IB-SEE-DICK"). I named my favorite cat Ebcdic. (Try getting that spelled correctly on a name tag!) Unicode is a huge movement in some data processing circles; see Unicode.org, dedicated to advancing Unicode.
The Shell Sort program in the book is an ideal first program. When I taught beginning programming to freshman college students, I devoted two weeks to teaching a sort program as a first example!
The book author (correctly) notes that the example shown in the bookwon't stop someone experienced in breaking encryption. In fact, it's one of several well-known methods (it's called the "shifter" method). An experienced programmer would normally assume that this common method was used. For a few more well known encyption techniques, try this page from the University of Saskatchewan!
