Figure 2-15. 5 1/4- and 3 1/2-inch floppy disks store programs and data,
and are easy to use and mail.
disk drive: a mechanism that rotates a storage disk and reads or writes data.
(d) Floppy disks come in two basic sizes: 5 1/4- and 3 1/2-inch
diskettes and hold from 360K to 1.4 megabytes of information. The 1K or kilobyte
equals 1,024 bytes. It takes one byte of space to store a character or letter. The word
"fox," for example, requires 3 bytes. (One source states that 1K or 1,024 bytes is equal
to about one double-spaced type-written page. This equivalency is helpful in
conceptualizing the value of 1K. But, in fact, the number of bytes actually needed to
store one double-spaced page will vary with the hardware and software you are using.
So, keep it in mind, but expect the actual number of bytes per page to vary from system
to system.) 1 megabyte equals 1,024K. Most users need at least two floppy disks or
one hard disk for their own use.
K (kilobyte): RAM and disk capacity are measured in kilobytes, 1K being the
equivalent of 1,024 bytes.
mB (megabyte): 1,000,000 bytes; 1 mB equals 1,024K; RAM and disk capacity
are measured in megabytes.
Figure 2-16. Working of a hard disk in a disk drive.