what exactly does a simple wipe do?

it says it's faster... does it permantly delete files? or are they just easier to recover?

also, what's wipe free space... is this nessasary to completly delete files?

The wipe modes are discussed here.

A single 1-pass "simple wipe" should make the files non-recoverable in a general sense. However with stuff being located in the MFT (which can't be touched) not everything can be successfully wiped out when for instance using wipe free space.

The wipe modes are discussed here.

A single 1-pass "simple wipe" should make the files non-recoverable in a general sense. However with stuff being located in the MFT (which can't be touched) not everything can be successfully wiped out when for instance using wipe free space.

cheers, i take it Normal file deletion can be retrieved easy enough...