2008 Oct 18
Floppy disks are removable magnetic read/write storage media. All floppies use 512 bytes/sector (see table below).
They have a mechanical means of write protecting them. The larger older floppies require tape to block the notch, while the new smaller floppies have a plastic tab that can be slid in its slot. In both case, covering the slot write protects the floppy (which also prevents it from being reformatted.
| Format | Tracks | Sectors / Track |
Total Sectors |
Usable Capacity |
Size |
|---|---|---|---|---|---|
| SSDD | 40 | 8 | 320 | 160KB | 5.25" |
| DSDD | 40 | 8 | 640 | 320KB | 5.25" |
| SSDD-9 | 40 | 9 | 360 | 180KB | 5.25" |
| DSDD-9 | 40 | 9 | 720 | 360KB | 5.25" |
| DSDD-9 | 80 | 9 | 1420 | 720KB | 3.5" |
| DSHD-15 | 80 | 15 | 2400 | 1.2MB | 5.25" |
| DSHD-18 | 80 | 18 | 2880 | 1.44MB | 3.5" |
| HD-36 | 80 | 36 | 5760 | 2.88MB | 3.5" * |
| SS__ | Single Sided |
| DS__ | Double Sided |
| __DD | Double Density |
| __HD | High Density |
2005-2008