Hardware Reference
In-Depth Information
The actual magnetic medium in both the 3 1/2-inch and 5 1/4-inch disks is constructed of
the same basic materials. They use a plastic base (usually Mylar) coated with a magnetic
compound.High-densitydisksuseacobalt-ferriccompound;extended-densitydisksusea
barium-ferricmediacompound.Therigidjacketmaterialonthe31/2-inchdiskshasocca-
sionally caused people to believe incorrectly that these disks are some sort of “hard disk”
and not really a floppy disk. The disk cookie inside the 3 1/2-inch case is just as flexible
as the larger 5 1/4-inch variety.
Tape Drives
Tape drives and media were once a somewhat popular form of magnetic storage for
backup use. Although the drives were expensive, the tape media was cheap, allowing
multiple backup sets to be inexpensively created. Unfortunately, as hard drive capacities
increased, the capacity of tape media could not keep pace, and using multiple tapes to
backup a single drive meant time-consuming and error-prone media swaps. The perform-
ance of tape drives also suffered in relation to hard disks, greatly increasing the time it
took for a backup to complete. Hard drives also become much less expensive, such that
it was cheaper and easier to simply purchase more hard drives for backups. Over time,
all these factors have caused tape backup drives and media to no longer be suitable for
standard desktop or laptop PC backups. Currently tape drives and media are only used for
high-end server backups.
