I wouldn't recommend learning from the ABS (or shellscripting from TLDP in general). It's full of bugs, errors, and just bad information in general. For this particular example, there's never really a case where you should depend on wordsplitting via IFS hacks to iterate over a scalar string variable. You can make it work, but you can't make it safe and will run into plenty of strange bugs. Bash on the other hand has other native tools and features to make splitting a string into a list safe, and the array datatype (which can store a list) which is the proper way to iterate over a collection.