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Computer Science IGCSEPDF 35
142 pagesrevision 46930
PDF 35
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The hard drive spins metal discs at high speed (typically
5400–7200 RPM) using a motor.
A read/write arm, controlled by an actuator, moves the head to
the data location.
Data is read and written using electromagnets.
Advantages
Disadvantages
Capacity - High storage
Cost - Low per gigabyte
Speed - Moderate read/write
access
Noise - Loud (spinning disks)
Reliability - Prone to mechanical failure
Durability - Moving parts can get damaged if dropped
Portability - Heavy & bulky making them less convenient
for transport