You can store a file either in the traditional NTFS file system or in the new WinFS data store just like you can store things in FAT32 or on CD-ROMs or in NTFS today. Normally, a file stored in NTFS is not visible in WinFS. Longhorn applications using the new WinFS APIs can access data stored either in WinFS or in NTFS. In addition, Longhorn applications can continue to use the Win32 API to access data stored in the NTFS file system More