File hiding based on FAT file system

With the rapid development of science and technology, people\´s privacy, as well as a great deal of important commercial and military information are more easily violated than ever before. So the technology of hiding files is particularly important. In this paper, through the analysis of FAT file system, two methods of hiding files have been propounded. The first method is to hide a file by using the clusters which are taged as "BAD CLUSTER" by us. The other method is to hide a file by using the remaining space of clusters. It is more suitable for hiding small files. We can make use of both these methods to hide any files in the FAT file system easily, quickly, thoroughly and safely, and achieve non-destructive recovery of the hidden file. Both of the methods are very practical in commercial, financial, military and other fields.