Earlier the USB file systems were formatted to FAT 32 systems. Microsoft then introduced the advanced version of FAT 32 file system that is the NTFS (New Technology File System). The NTFS eventually increased the performance of the file operations. Then it was ExFAT file system added by Microsoft for optimizing the flash drives.
NT File System (NTFS)
NTFS has got advanced features as file security and permissions, disk quota limits, quick error recovery by a change of journal during crashes, shadow copies (for backup), encryption, hard links etc. Your system partitions will be NTFS formatted and if you add any external device to the computer then you should proceed with NTFS file system for the drive. This NTFS is supported on both Mac OS X and Windows operating system. However, Mac has only read permission for files that are NTFS formatted; meaning you will be able to view the file on Macintosh but you do not have any permission to edit or make changes to the file contents.
ExFAT (Extended File Allocation Table)
The ExFAT system was added to the older Windows versions as Vista and XP. This file system is specially optimized for the flash drives. It overcomes all the limitations found in the FAT 32 systems. With ExFAT system you can store or transfer files larger than 4GB; offering large size limit for files and partitions. Unlike NTFS, Mac has full support to read and write with ExFAT.
Taking USB drives for a test, if we see benchmark results for a file delete operation – NTFS delivers 68% of performance while that of ExFAT is 24%. Performance analysis can be made for the drives by considering operations like reading small files, large files or medium sized files. NTFS shows high performance and can be used while dealing with tens of thousands of files whilst ExFAT can be used for about thousand files. You can suitable choose between NTFS and ExFAT systems and reformat. Before you reformat the drive it is essential to back up the drive contents. It is because disk contents are wiped with a format or reformat action. In case if you mistakenly format the drive then use NTFS or ExFAT data recovery programs to retrieve files from it.