Have you ever thought what happen if you lose your notebook computer? All your documents, images, videos can be easily read by evil-wisher. Even your emails can be read!
Stealth Storage mounts a pseudo-disk into the system. Entire pseudo-disk content is stored in the only file called disk container. Disk container file is strongly encrypted. So, all the data stored on pseudo-disk is encrypted as well. You can work with pseudo-disk as usual (create/delete/change files, install programs, format the disk etc) you will not feel the difference from real disk, except that nobody will read your private data without specifying a password.