NTFS vs FAT

FAT16

FAT32

NTFS

1.) The FAT16 file system was introduced way back with MS–DOS in 1981, and it's showing its age. It was designed originally to handle files on a floppy drive, and has had minor modifications over the years so it can handle hard disks, and even file names longer than the original limitation of 8.3 characters, but it's still the lowest common denominator. The biggest advantage of FAT16 is that it is compatible across a wide variety of operating systems, including Windows 95/98/Me, OS/2, Linux, and some versions of UNIX. The biggest problem of FAT16 is that it has a fixed maximum number of clusters per partition, so as hard disks get bigger and bigger, the size of each cluster has to get larger. In a 2–GB partition, each cluster is 32 kilobytes, meaning that even the smallest file on the partition will take up 32 KB of space. FAT16 also doesn't support compression, encryption, or advanced security using access control lists.
2.) A FAT volume has a maximum size of 2GB and supports MS-DOS as well as being used for some dual boot configurations, but backward compatibility is about the only reason one can think of that FAT should ever be used, other than for the occasional floppy diskette.

1.) The FAT32 file system, originally introduced in Windows 95 Service Pack 2, is really just an extension of the original FAT16 file system that provides for a much larger number of clusters per partition. As such, it greatly improves the overall disk utilization when compared to a FAT16 file system. However, FAT32 shares all of the other limitations of FAT16, and adds an important additional limitation—many operating systems that can recognize FAT16 will not work with FAT32—most notably Windows NT, but also Linux and UNIX as well. Now this isn't a problem if you're running FAT32 on a Windows XP computer and sharing your drive out to other computers on your network—they don't need to know (and generally don't really care) what your underlying file system is.

1.) The NTFS file system, introduced with first version of Windows NT, is a completely different file system from FAT. It provides for greatly increased security, file–by–file compression, quotas, and even encryption. It is the default file system for new installations of Windows XP, and if you're doing an upgrade from a previous version of Windows, you'll be asked if you want to convert your existing file systems to NTFS. Don't worry. If you've already upgraded to Windows XP and didn't do the conversion then, it's not a problem. You can convert FAT16 or FAT32 volumes to NTFS at any point. Just remember that you can't easily go back to FAT or FAT32 (without reformatting the drive or partition), not that I think you'll want to.
The NTFS file system is generally not compatible with other operating systems installed on the same computer, nor is it available when you've booted a computer from a floppy disk. For this reason, many system administrators, myself included, used to recommend that users format at least a small partition at the beginning of their main hard disk as FAT. This partition provided a place to store emergency recovery tools or special drivers needed for reinstallation, and was a mechanism for digging yourself out of the hole you'd just dug into. But with the enhanced recovery abilities built into Windows XP (more on that in a future column), I don't think it's necessary or desirable to create that initial FAT partition.



FAT16, FAT32 and NTFS each use different cluster sizes depending on the size of the volume, and each file system has a maximum number of clusters it can support. The smaller the cluster size, the more efficiently a disk stores information because unused space within a cluster cannot be used by other files; the more clusters supported, the larger the volumes or partitions that can be created.
The table below provides a comparison of volume and default cluster sizes for the different Windows file systems still commonly in use:


Which File System to Choose?
As much as everyone would like for there to be a stock answer to the selection question, there isn't. Different situations and needs will play a large role in the decision of which file system to adopt. There isn't any argument that NTFS offers better security and reliability. Some also say that NTFS is more flexible, but that can get rather subjective depending on the situation and work habits, whereas NTFS superiority in security and reliability is seldom challenged. Listed below are some of the most common factors to consider when deciding between FAT32 and NTFS.
· Security
FAT32 provides very little security. A user with access to a drive using FAT32 has access to the files on that drive.
NTFS allows the use of NTFS Permissions. It's much more difficult to implement, but folder and file access can be controlled individually, down to an an extreme degree if necessary. The down side of using NTFS Permissions is the chance for error and screwing up the system is greatly magnified.
Windows XP Professional supports file encryption.
· Compatibility
NTFS volumes are not recognized by Windows 95/98/Me. This is only a concern when the system is set up for dual or multi-booting. FAT32 must be be used for any drives that must be accessed when the computer is booted from Windows 95/98 or Windows Me.
An additional note to the previous statement. Users on the network have access to shared folders no matter what disk format is being used or what version of Windows is installed.
FAT and FAT32 volumes can be converted to NTFS volumes. NTFS cannot be converted to FAT32 without reformatting.
· Space Efficiency
NTFS supports disk quotas, allowing you to control the amount of disk usage on a per user basis.
NTFS supports file compression. FAT32 does not.
How a volume manages data is outside the scope of this article, but once you pass the 8GB partition size, NTFS handles space management much more efficiently than FAT32. Cluster sizes play an important part in how much disk space is wasted storing files. NTFS provides smaller cluster sizes and less disk space waste than FAT32.
In Windows XP, the maximum partition size that can be created using FAT32 is 32GB. This increases to 16TB (terabytes) using NTFS. There is a workaround for the 32GB limitation under FAT32, but it is a nuisance especially considering the size of drives currently being manufactured.
· Reliability
FAT32 drives are much more susceptible to disk errors.
NTFS volumes have the ability to recover from errors more readily than similar FAT32 volumes.
Log files are created under NTFS which can be used for automatic file system repairs.
NTFS supports dynamic cluster remapping for bad sectors and prevent them from being used in the future.
The Final Choice

As the prior versions of Windows continue to age and are replaced in the home and workplace there will be no need for the older file systems. Hard drives aren't going to get smaller, networks are likely to get larger and more complex, and security is evolving almost daily as more and more users become connected. For all the innovations that Windows 95 brought to the desktop, it's now a virtual dinosaur. Windows 98 is fast on the way out and that leaves NT and Windows 2000, both well suited to NTFS. To wrap up, there may be compelling reasons why your current situation requires a file system other than NTFS or a combination of different systems for compatibility, but if at all possible go with NTFS. Even if you don't utilize its full scope of features, the stability and reliability it offers make it the hands down choice.