Page 67 - open office
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Platter
Spindle
Head
Head Actuator Arm
Actuator Axis
& Pivot Screw
Voice Coil Power Connector
Actuator
Jumper Block
Ide Connector On Printed
Circuit Board (Interface)
Do you know?
Hard Disk is also known as Winchester Disk.
Optical Disc: Optical Disc is commonly used as an external storage device in which a laser beam helps to read
data from the at surface of the optical disc.
CD: CD or Compact Disc is a common optical disc. It is made up of lightweight plastic
material with a chemical coating on one side where data is stored.
It is inserted into a CD/DVD drive or CD/DVD writer of a CPU. In CD ROM (Compact
Disc Read Only Memory) data can only be read whereas in CD writer, data can be read
and written as well. The capacity of 120 mm standard CD is 700 MB.
DVD: DVD or Digital Versatile/Video Disc is an optical disc that looks like a CD but has
a capacity to store data up to 17.1 GB.
To read information stored in a DVD, it has to be inserted into a DVD ROM or DVD
Writer or DVD player (to copy information on a DVD, one has to use a DVD writer).
Blu-ray Disc: Blu-ray Disc can store data of up to 128 GB. It has been developed
by the Blu-ray Disc Association (BDA). It is more advanced than CDs or DVDs.
Blue-violet laser is used to read or write data on the Blu-ray disc.
Do you know?
Diameter of a CD, DVD or Blu-ray disc is 120 mm. DVD can also be of 80 mm diameter that can hold
data upto 1.5 GB.
CDs can be used or played in a DVD-ROM or a DVD player but DVD cannot be operated in a CD
player.
A combo drive is a device which contains all the features of a CD-Writer and a DVD ROM.
Information & Communication Technology 67

