largedarryl on 13 July 2009
Superchunk is correct. When your hard drive (SD card, floppy, etc.) has a file system, it is basically a section of the memory is basically a large list of all the files and the address on the disc. So basic deletes only remove the pointer to those files (really quick to write less than 1kB of data). If you are truly attempting to get rid of the data, a true full format is required or the other non-standard way would be to fill your hard drive up with duplicate data (essentially rewriting all the non-allocated memory).
