An obvious place to use a Bourne shell is to step through a list of arguments - from the command line or a variable. But combine the loop with and , and the loop will step through the words on standard input.
Here's an example:
for x in `cat` do ...handle $x done
Because this method splits the input into separate words, no matter how many words are on each input line, it can be more convenient than a while loop running the read command, as in article 9.20. When you use this script interactively though, the loop won't start running until you've typed all of the input; using while read will run the loop after each line of input.