Because it is easily erased because it is on magnetic tape so if it were to go near a magnet it would be erased.
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They may also degrade with time - but whether that is more serious than the computer manufacturers making the equipment obsolete within only a few years so you can't read them anyway, I'll leave others to decide!
"Permanent storage", because the data does not disapear when the power is turned off.
Permanent storage device such as a hard drive.
Floppy disks
Secondary Storage
Magnetic
Floppy disks use magnetic disk to store the data.
They can hold more data than floppy disks and computers aren't really made with floppy disk entrances :)
Data storage devices.
they are floppy disks
Floppy drive was the first storage with portable data storage capacity.. However the data storing capacity of floppy drive is not enough but in early days it helped a lot..
Floppy disks were an older technology then diskettes. They were computer storage disks encased in a soft plastic envelope (hence "floppy") that had a bigger diameter than the diskettes which were packaged in a hard plastic cartridge.
A storage device is any computer hardware meant to store data permanently or semi-permanently. This includes, but is not limited to hard disks, floppy disks, cdroms and DVDs.