Formatting a drive does **not** remove any data.
The data is still there, but in an unorganized fashion.
Any undelete software (example: GetDataBack NTFS) can recover the files. It also works perfectly well on encrypted Truecrypt volumes (checked myself).
Also, one need to be careful when selling a hard drive, because any data, that hasn't been securely erased or filled with zeros, can be easily resurrected.
The data is still there, but in an unorganized fashion.
Any undelete software (example: GetDataBack NTFS) can recover the files. It also works perfectly well on encrypted Truecrypt volumes (checked myself).
Also, one need to be careful when selling a hard drive, because any data, that hasn't been securely erased or filled with zeros, can be easily resurrected.
I red somewhere that the only 100% sure way to erase data on a disk is to expose it to a 1,200°C temperature.
Well FBI / CIA may be able to read the data after you zero-fill it once or twice.
To absolutely securely erase the data, you need to do at least several passes, each writing random data on the drive. There is a specialized software avaiable for this, however You can just use this command several times:
Code:
dd if=/dev/urandom of=/dev/device
on Linux. Just boot up an Ubuntu LiveCD. Replace "/dev/device" with the disk you want to erase (eg. /dev/sda or /dev/sdb).
Of course make sure first if you are cleaning the right disk - any data will be irreversibly lost: You have been warned.
