A
device, like a tape recorder, that
reads data from and
writes it onto a
tape. Tape drives have data capacities of anywhere from a few hundred
kilobytes to several
gigabytes. Their transfer speeds also vary considerably. Fast tape drives can transfer as much as 20MB (
megabytes) per second.
The disadvantage of tape drives is that they are sequential-access devices, which means that to read any particular block of data, you need to read all the preceding blocks. This makes them much too slow for general-purpose storage operations. However, they are the least expensive media for making backups.