Acer TravelMate P255-MP - Manual (Page 51)

Acer ProShield - 51
Data Protection
Here you can select files for encryption or decryption, and manage
your Personal Secure Drive.
Data Removal
Here you can select files to be completely removed from the hard
disk. The File Shredder overwrites the data to make recovering the
data impossible.
Warning
Make sure you select only the information you want to shred. Once you
have shredded a file or folder, it is impossible to recover the data.