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1.2 MB 5.25" Floppy

The high density 1.2 MB floppy disk debuted in the IBM AT in 1984, as a standard feature (the 360 KB floppy was optional). The increase in capacity of this disk, over 200% compared with the 360 KB version, all but obsoleted the smaller format rather quickly. The 1.2 MB floppy disk can still read and write 360 KB floppies, but problems can occasionally result. Since the floppy uses a higher bit density, the 1.2 MB floppy requires a floppy disk controller capable of 500 Kbits/s data transfer. Virtually all newer controllers support this rate.

At the time that this disk was introduced, it was considered relatively "roomy". Compared to a 20 MB hard disk, a 1.2 MB floppy is pretty decent storage. The 5.25" disk has all but died out due to the physical advantages of the 3.5" formats. Still, some older PCs continue to use their 1.2 MB disks to this day.

Note: Look here for specifications on all of the floppy disk formats.

Next: 720 KB 3.5" Floppy

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