Research on secure destruction of digital information

This paper is about an interdisciplinary knowledge relating to Computer Science and Solid State Electronics. The normal FORMAT or DELET operation in computer can not verily eras the data on the hard disk. By using precision instruments, the data could be recognized and recovered. Based on the intensive study in characteristic of magnetic medium and the data encoding rules, this paper represents an effective theory to destruct data from hard disk without specialized equipment. And finally, it proposes a feasible solution for the data destruction software on Linux and Windows operating system.