El-Shorouk Academy
Higher Institute for Computer &
Information Technology
Department of Computer Science
Acad. Year : 2011/ 2012
Term
: First
Year
: First
Course
: Introduction in English
Unit (12)
Sheet -12-
Complete the following sentences:1. CD stands for .....Compact Disc.....
2. CD-ROM stands for .....Compact Disc-Read Only Memory......
3. CD-R stands for .....Compact Disc-Recordable......
4. CD-RW stands for .....Compact Disc-ReWritable......
5. DVD stands for ....Digital Versatile Disc.......
6. DVD-ROM stands for .....Digital Versatile Disc-Read Only Memory......
7. MO drive stands for .....Magneto-Optical drive......
8. DAT stands for ......Digital Audio Tape.......
9. WORM stands for ......Write Once, Read Many.......
10. One ......CD-ROM disc...... is equivalent to 500 floppies.
11. One DVD-ROM disk is equivalent to 25 times of ....an CD-ROM disc......
Read these sentences and decide if they are true (T) or false (F)
and correct the wrong ones:1. Magnetic disks can store information at much higher densities than optical disks.(F)
AnswerOptical disks can store information at much higher densities than
magnetic disks.
2. Optical drives are slower than hard drives.(T)
3. CD-ROM drives can't play audio CDs.(F)
AnswerCD-ROM drives can play audio CDs.
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4. CD-RW disks are the modern version of old WORM disks.(F)
AnswerCD-R disks are the modern version of old WORM disks.
5. Magneto-optical drives use both a laser and an electromagnet to record
information.(T)
6. MO disks are read only disks.(F)
AnswerMO disks are rewritable disks.
7. DVD-ROM drives can't play music CDs.(F)
AnswerDVD-ROM drives can play music CDs.
8. A typical CD-ROM can hold up to 100 MB.(F)
AnswerA typical CD-ROM can hold up to 650 MB.
9. You need a hard disk drive to read CD-ROM disks.(F)
AnswerYou need a CD-ROM drive(or DVD-ROM drive) to read CD-ROM
disks.
10. The data on a CD-ROM can be changed or written to.(F)
AnswerThe data on a CD-ROM is a read-only data.
11. A CD-ROM is a good way of storing large amounts of information (images, sounds
and applications).(T)
12. CD-R disks are used to backup hard disks or to archive information.(T)
13. A DVD-ROM can hold 17 GB.(T)
14. A CD-ROM disk is very different from a compact music disk.(F)
AnswerA CD-ROM disk is the same as a compact music disk.
15. The data on a CD-ROM is read with a laser beam.(T)
 Compare between the various types of optical drives (CD-ROM, CDRecorder, DVD and Magneto-Optical).
CD-ROM
Technical specifications
Use
 CD-ROM stands for Compact
Disc-Read Only Memory.
 CD-ROM
systems
offer everything, from
shareware programs to
dictionaries
and
encyclopedias, from
multimedia databases
to 3-D games.
 One CD-ROM disk can hold up to
650 MB.
 CD-ROM drives can play music
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CDs while you work.
 CD-ROM disk is a read-only disk
that we can't write anything onto it.
CD-Recorder
 It comes on two different forms:
CD-R and CD-RW.
 CD-R stands for Compact DiscRecorder.
 CD-R disks are the modern version
of old WORM (Write Once, Read
Many) disks.
 ACD-R can be used to
back up hard disks or
to
distribute
and
archive information.
 A CD-RW can be
used to save, update,
delete and retrieve any
data.
 CD-RW stands for Compact DiscReWritable
 CD-RW disks can be erased and
re-used.
DVD
 It stands for Digital Versatile Disc.
 It can hold 17 GB, bout 25 times a
CD-ROM.
 It can store a large
amount of multimedia
software.
 DVD-ROMs are read-only devices
that we can't write anything onto it.
 DVD-ROM can play music CDs
and CD-ROMs.
 Companies also produced DVD-R
and DVD-RW.
Magneto-optical
 MO drives use both a laser and an
electromagnet
to
record
information.
 MO disks are rewritable that they
can be written to, erased, and then
written again.
 It comes in two formats: (a) 5.25"
cartridges can hold more than 5.2
GB. (b) 3.5" floptical disks have a
capacity of 230 MB to 1.3 GB.
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 They are ideal for
back-up and portable
mass storage.