Zero-filling the hard disk

[Mohan Giri]

In zero-filling process of the hard disk( Commonly known as formatting a hard disk) every sectors will be filled with zero or bad sectors which are marked at the factory itself can also filled with zeros???????????????

 

[TheMajor]

Formatting is not the same as zero-filling. Formatting just removes the files from the file table. Zero-filing overwrites the sectors multiple times to get rid of the data.
I think both formatting and zer-filling utilities skip bad sectors.