Private information on public computers

["Steven Meyer" <meysteven () gmail com>]

Hello list,
A lot of collaborators in the company do some office work (word,
excel, PowerPoint) at home or on "public computer".
Since some of there work information is confidential, I was wondering
what kind of information (if no key loggers are installed,) could be
reviled ( there always save there document on a usb stick,) after
there have done with they work. I know for example in the recent files
menu, you can find the name of the last accessed files. But is they
some temp files of the document that are stored one the hard drive.
The real Question would be: what kind of information could someone
retrieve from the computer after the collaborators work is done and
saved on a usb stick. And what would there need to do  for the
computer to be completely cleaned of all information about they work.
Thanks for all help
Steven Meyer