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ILLUSTRATION
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Assume that our computer system is composed of the following components:
COMPUTER SYSTEM
The Central Processing Unit, CPU,
CPU
and primary memory which is fast but not permanent,
Memory
both of which are controlled by an operating system such as UNIX !
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Operating System
U N I X
Connected to the system may be several terminals!
Terminals
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| Terminal |
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A disk drive is also a part of the computer system. The disk
drive constitutes the secondary memory which is nonvolatile
(retains data when the power supply is disconnected), and is much
larger than primary memory. This type of memory is slower to access!
Disk Drive
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/ \
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\ /
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The disk drive normally holds all of the files. It is
referred to as secondary storage.
/ File_1 \
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| File_X |
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| File_Y |