3. Storage Devices
• The storage devices store
data –even when the
computer is turned off.
• It is used to keep important
data and files which are of
regular use on permanent
basis.
8. Floppy DiskFloppy Disk
Floppy Disk –is a removable disk
that everyone is familiar with. Since
it has a small capacity, it is typically
used to store documents so that
they can be used on more than one
computer.
12. CD Structure
• A CD is flat, round, portable metal disc,
which is coated with a thin metal or plastic.
• It is usually 0.75 inches in diameter.
13.
14.
Compact Disc - read only memory (write
once)
Data is encoded and read optically with a
laser
Can store around 600 and 700 MB data
Compact Disc - read only memory (write
once)
Data is encoded and read optically with a
laser
Can store around 600 and 700 MB data
15. :-Compact Disc read-only memory is a Compact Disc that
contains data accessible by a computer.
•Firstly the Compact Disc format was designed for music
storage and playback,
•Later the format was adapted to hold any form of binary
data.
CD-ROM
16. •CD-ROM are popularly used to distribute computer
Software, including games and Multimedia
applications, though any data can be stored (up to
the capacity limit of a disc). Some CDs hold both
computer data and audio with the latter capable of
being played on a CD player, whilst data (such as
software or digital video) is only usable on a
computer (such as PC CD-ROMs. These are called
Enhanced CDs.
17. Reading Speed
• Reading speed is measured in kB/s
• Reading speed determines the transfer of
data in one second.
• 1× or 1-speed which gives a data transfer
rate of 150 kB/s in the most common data
format.
18. Advantages of CD-ROM
• Large storage space
• Compact and light
• Can be manufactured on a large
scale
20
20. Summary
• Compact Disk is a type of optical storage.
• It holds data through physical marks.
• Its is played in a CD-Player, and is read at
different speeds.
• Files system is required to write data on
CD by different methods.
• CDs are compact storage devices that can
be moved from on place to another easily.
25. DVDs (Digital Versatile
Disc or Digital Video Disc)
DVD, is an optical disc storage
media format, and was invented
in 1995. Its main uses are video
and data storage. DVDs are of the
same dimensions as compact
discs (CDs), but store more than
six times as much data.
DVD, is an optical disc storage
media format, and was invented
in 1995. Its main uses are video
and data storage. DVDs are of the
same dimensions as compact
discs (CDs), but store more than
six times as much data.