Take a look at this screenshot: New “Guest Account” feature on the new build of Mac OS X. Now, for those who don’t want to see just another screenshot, here is the words that took my attention:
When a guest user logs out, all information and files in the guest account’s home folder are deleted.
(Emphasis mine). Now, Windows has no concept of “Home” but call directories “folders”; Unix has a “Home” for each user, but call it “home directory”. Mac OS X developers seem to have merge those in one, calling “home folder”.