Disk Size Limit 32MB -- This applies Only to MSDOS 3.3 MSDOS 2 and 3 used the FAT12 system originally developed for use with floppy disks. FAT12 uses 4096 clusters of up to 16 sectors per cluster with a maxium size of 16MB. FAT12 is still used by Microsoft Operating systems as recent as Windows 98 for hard drive partitions of 16MB or less using clusters of up to 8 sectors. MSDOS 3.3 introduced the ability to use Extended Partitions and the use of FAT16. However, the initial version of FAT16 only addressed about 65536 sectors. Extended partitions allowed drives larger than 32MB to be configured with multiple 32MB FAT12 partitions up to the limit of 24 partitions imposed by the practice of assigning each partition a unique drive letter C-Z. MSDOS 4.0 introduced 32 bit sector addressing in FAT16 which could accomodate primary and extended partitions of up to 2.14GB each

See also FAT12

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