It is very simple to hide folders in Linux. Simply put a "." before the folder name.
for example: /home/user/.secret
The folders "home" and "user" are visible but the sub-folder "secret" is not visible.
You can also set permissions on the folder(s) that only the user who owns the folder can view it. This won't help if they have access to your account. To do this just right click on the folder and go to the permission tab (assuming your using a desktop and not the command line.)
Hope this helps
