exFAT

exFAT has been implemented into Mac OS X since 10.6.5 (around 2010 or so).

exFAT has probably disadvantages over HFS+, journaling or permissions or playing well, or at all, with UNIX for example, thus it was not used. MS still uses NTFS too, and it is an old file system (though not as old as HFS).
exFAT also took a while to be implemented into Windows 5.1 or Windows 6.

Format A Hard Drive Using Disk Utility (which is in your /Applications/Utilities folder)

Choose the appropriate format:

HFS+ (Hierarchical File System, a.k.a. Mac OS Extended (Journaled) Don't use case-sensitive)

• Read/Write HFS+ from native Mac OS X
• Required for Time Machine or Carbon Copy Cloner or SuperDuper! backups of Mac OS X system files.
  [*]To Read/Write HFS+ from Windows, Install MacDrive
  [*]To Read HFS+ (but not Write) from Windows, Install HFSExplorer
• Maximum file size: 8EiB
• Maximum volume size: 8EiB
• Mac OS X: Mac OS Extended format (HFS Plus) volume and file limits
• You can use this format if you only use the drive with Mac OS X, or use it for backups of your Mac OS X internal drive, or if you only share it with one Windows PC (with MacDrive installed on the PC)

NTFS (Windows NT File System)

• Read/Write NTFS from native Windows.
• Read only NTFS from native Mac OS X
  [*]To Read/Write/Format NTFS from Mac OS X, here are some alternatives:
  • For Mac OS X 10.4 or later (32 or 64-bit), install Paragon ($19.95) (Best Choice for Lion and Mountain Lion)
  • For Mac OS X 10.5 and later, including Lion, FUSE for OS X
  • For 32-bit Mac OS X, install NTFS-3G for Mac OS X (free) (does not work in 64-bit mode)
  • Some have reported problems using Tuxera (approx $36), which is an enhanced version of NTFS-3G with faster performance.
  • Native NTFS support can be enabled in Snow Leopard and later versions, but is not advisable, due to instability.
• AirPort Extreme (802.11n) and Time Capsule do not support NTFS
• Maximum file size: 16 TB
• Maximum volume size: 256TB
• You can use this format if you routinely share a drive with multiple Windows systems.

exFAT (FAT64)

• Supported in Mac OS X only in 10.6.5 or later.
• Not all Windows versions support exFAT. See disadvantages.
• exFAT (Extended File Allocation Table)
• AirPort Extreme (802.11n) and Time Capsule do not support exFAT
• Maximum file size: 16 EiB
• Maximum volume size: 64 ZiB
• You can use this format if it is supported by all computers with which you intend to share the drive. See "disadvantages" for details.

FAT32 (File Allocation Table)

• Read/Write FAT32 from both native Windows and native Mac OS X.
  [*]Maximum file size: 4GB.
• Maximum volume size: 2TB
• You can use this format if you share the drive between Mac OS X and Windows computers and have no files larger than 4GB.

HFS+ has Posix semantics. ExFAT doesn't. That alone is a huge reason why ExFAT won't work as the "go to" filesystem for any real work on a Mac. ExFAT is good for transferring data between Mac and Windows, but it's not useful for any real work on a Mac such as backups.

I think the reason ExFAT was created was so that you could have a flash drive filesystem that supported files over 4GB for things like video cameras and other portable devices that create large files. But the filesystem is not appropriate for general computer use since ExFAT also doesn't feature journalling.

In this case "newer" doesn't necessarily mean "better" for all uses. ExFAT is better for simple data transfer. That's it.

mfram said:

...

In this case "newer" doesn't necessarily mean "better" for all uses. ExFAT is better for simple data transfer. That's it.

Click to expand...

Along these lines, I am convinced that exFAT is less reliable than the older FAT filesystems. exFAT's disadvantages in GGJstudios's post link to a Wikipedia page that includes this point. FAT32 and its siblings have two alternating File Allocation Tables that allow file system recovery. exFAT uses a single FAT and space map.

The File Allocation Table is not a robust paradigm. I have great difficulty understanding why I should use a file system with only one FAT when NTFS is a more robust file system. When I need a computer, I use my Mac and format its volumes HFS+. But, when I need to exchange files with Windows users, I use my Mac running NTFS-3G to format my cross-platform volumes as NTFS.