Disk CleanUp is a small disk utility designed to clear previously deleted files. Deleting a file will normally just remove the file's directory entry, but the data itself still remains on the disk. CleanUp will completely eliminate the contents of your deleted files. Disk CleanUp provides options to specify an NSA approved disk erasure method and background execution priority. Disk CleanUp works with any FAT16 or FAT32 hard drive as well as NTFS