CHAPTER 7
Storage
Katie Moody
Storage
• Storage holds data, instructions, and
information for future use.
• Every computer uses storage to hold
software.
Storage Terms
• A storage medium is the physical material on
which a computer keeps data, instructions, and
information (i.e) Zip disks, hard disks, CDs,
DVDs etc…).
• Capacity is the number of bytes (characters) a
storage medium can hold.
• A storage device is the computer hardware that
records and/or retrieves items to and from storage
media.
Storage Terms continued…
• Writing is the process of transferring data
instructions, and information from memory to a
storage medium
• Reading is the process of transferring these items
from a storage medium into memory.
• Access time measures the amount of time it takes a
storage device to locate an item on a storage
medium, or the time required to deliver an item
from memory to processor.
Floppy Disks
• A floppy disk, also
called a diskette, is a
portable, inexpensive
storage medium that
consists of a think,
circular, flexible
plastic Mylar film
with a magnetic
coating enclosed in a
square-shaped plastic
shell.
Floppy Disk Drives
• A floppy disk drive is a
device that reads from
and writes on a floppy
disk. A user inserts a
floppy disk into and
removes it from the
floppy disk drive.
ZIP Disks
• A ZIP disk is a type of portable magnetic
media that can store from 100 MB to 750
MB of data.
• A larger capacity Zip disk can hold about
500 times more than a standard floppy disk.
Hard Disks
• A hard disk is a
storage device that
contains one or
more inflexible,
circular platters that
store data,
instructions, and
information.
Types of Hard Disks
• External Hard
Disk
• Removable Hard
Disk
- a separate freestanding
hard disk that connects
with a cable to a USB port
on the system unit.
- a hard disk that you insert
and remove from a hard
drive.
• Advantages of
External and
Removable Hard
Disks
Hard Disk Controllers
Disk Controllers
EIDE
SCSI
(Enhanced Integrated Drive Electronics)
-can support up to four hard disks
-provides connections for CD and DVD drives
(Small Computer system Interface)
-can support up to eight or fifteen peripheral devices
-faster than EIDE controllers
Internet Hard Drives
• A service on the web that provides storage to
computer users, usually for a minimal fee.
• Reasons for Use:
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–
–
–
–
Access files on the internet
Saves time
Allows others to access files
View data immediately
Store offsite backup for data
CDs and DVDs
• Types of optical
storage media
• Primarily store
software, movies,
pictures, and music
• Can be read only or
have read/write
capabilities.
-The drive designation of a CD or DVD drive
usually follows alphabetically after that of all the
hard disks and portable disks.
-Are not magnetic media, rather they are optical
media, in which information is stored in
microscopic pits created by lasers.
-Properly cared for CDs and DVDs are guaranteed to
last five years.
CD-ROMs
(Compact disc read-only memory)
• Type of optical disk
that uses laser
technology to store
data.
• Can contain audio,
text, graphics, and
video.
• To read items stored
on a CD-ROM, insert
the disc into a
CD-ROM drive
Types of CDs
Picture CDs
CD-Rs
CD-RWs
-compact disc that stores digital
versions of a single roll of film.
(Compact disc-recordable)
(Compact disc rewritable)
DVD-ROMs
(Digital Versatile disc-ROM)
• An extremely high
capacity optical
disk capable of
storing 4.7 GB to
14 GB.
• Goal is to meet the
needs f home
entertainment ,
computer usage,
and and business
data with the use of
a single medium.
Tapes and PC Cards
• Tapes are magnetically • PC cards are thin
coated ribbon of
credit-card sized
plastic capable of
devices that add
storing large amounts
additional storage,
of data at a low cost.
memory, and other
capabilities.
• Used in tape drives.
Miniature Mobile Storage Media
•
•
•
•
PDA’s
Digital Cameras
Music Players
Smart Phones
Smart Cards
• Similar to the size of a credit card or an
ATM card, it stores data on a thin
microprocessor embedded in the card.
• Popular uses include pre-paid telephones,
digital cash, and storage of health care
information.
Microfilm
- a 100-215 foot roll of
film
Microfiche
- a small sheet of film,
usually about 4 inches
by 6 inches.
Libraries use these media to store back issues
of newspapers, magazines, and genealogy
records.