> One last thing I need to know: if "file-v" contains line by line
> listings of email addresses of those who sent in votes, and "file-p"
> is a line by line listing of email addresses of potential friends,
> some of whom may have voted yes already, what do I do to get a file
> containg what's in the second file but not the first (In terms a child
> could understand, given a minimal exposure to unix)? Thanks.

Take a look at the COMM(1) command.  I think what you want is:

	comm -13 file-v file-p

Each file must be sorted, and have duplicates removed first.  To do so,
you can use:

	sort -u  file-v>temp-v
	sort -u  file-p>temp-p
	comm -13 temp-v temp-p

The output will be offset, due to the way COMM(1) works, so you may need
to edit it afterward.

Slightly more complex, but possibly giving better results (in the sense
that the output will not be offset) might be:

(sort -u file-v;sort -u file-p)|uniq -u

The output will be a list of those addresses which occur exactly once.
It depends on file-v being a strict subset of file-p, since it will give
you those addresses that are not repeated, which would only be the ones
you want if you can assume that the temp-v addresses have come from the
set of temp-p addresses.  Otherwise, you'll get false positives (those
addresses representing people who have voted, but were not included in
the file-p list).