command thread help

If /etc/passwd is backed up every week, what will be the command to display the changes between the backed up version and the current file?

Your other thread confirms that this is homework. Please tell us more about the class and what you have studied so far. Also what reference materials, books, etc. they are using.

Here is a VERY big hint:
http://www.google.com/search?hl=en&q...US235&ie=UTF-8

I found this by entering "compare files linux" into a Google search.