3. The Computer Defined
Electronic device
Converts data into information
Modern computers are digital
Two digits combine to make data (0, 1)
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4. The Computer Defined
Older computers were analog
A range of values made data
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5. The Computer Defined
Older computers were analog
A more manageable type -- the old-fashioned slide rule
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7. CPU
It is a core component of the computer. It executes user’s
instructions and processes calculations.
Like the chief commander of the army, the CPU controls and
coordinates various devices in the computer system.
Without the CPU, the devices cannot work together and so
the computer cannot function.
It is often a etched on a chip and is usually called a
microprocessor.
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8. Basic units of CPU
It has basically to main units
CU(Control Unit)
ALU(Arithmetic and Logic Unit)
Control
unit
Arithmetic
and logic
unit
Some
registers
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9. Control Unit
The control unit executes the instructions, sends control
signals to and receive control signals from peripheral
devices.
In other words, it controls the whole computer, and
directs the entire system to carry out instructions.
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10. Arithmetic and Logic Unit
Arithmetic and
Logic Unit
Arithmetic unit
Logic unit
handles arithmetic
calculations
performs logical
calculations and makes
judgement like “if A > B is
true”.
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11. Registers
When the control unit and the arithmetic and logic unit
operate, they store the information and instruction temporarily
in registers.
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12. Program Executions
The diagram shows how the CPU executes an instruction:
Main memory
Fetch
Arithmetic and
logic unit
Control unit
ExecuteDecode
This is called machine
cycle.
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Before a computer executes instructions, they are first
placed in the main memory.
13. Fetching
Program Executions
The control unit gets the next program instruction from the
main memory.
Decoding
The control unit decodes what the instruction means.
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14. Executing
Program Executions
The ALU executes arithmetic and logical instructions.
It means that the ALU controls and performs the actual
operation on the data.
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16. Computers for Individual Use
Computers can
be shared by
multiple users
but can be used
by only one
person at a time.
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17. Computers for Individual Use
Although PCs are used by individuals,
they also can be connected together to create networks.
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18. Computers for Individual Use
Desktop computers
The most common type of computer
Sits on the desk or floor
Performs a variety of tasks
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19. Computers for Individual Use
Desktop computers
Different design types
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20. Computers for Individual Use
Workstations
Specialized computers
Optimized for science or graphics
More powerful than a desktop
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21. Computers for Individual Use
Notebook computers
Small portable computers
Weighs between 3 and 8 pounds
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22. Computers for Individual Use
Notebook computers
About 8 ½ by 11 inches
Typically as powerful as a desktop
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23. Computers for Individual Use
Tablet computers
Newest development
in portable
computers
Input is through
a pen
Run specialized
versions of office
products
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24. Computers for Individual Use
Handheld computers, palm computer
Very small computers
Personal Digital Assistants (PDA)
Note taking or contact management
Data can synchronize with a desktop
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25. Computers for Individual Use
Smart phones
Hybrid of cell
phone and PDA
Web surfing,
E-mail access
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26. Computers for Organizations
Network servers
Centralized computer
All other computers connect
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27. Computers for Organizations
Network servers
Flexibility to different kinds of tasks
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Computers for OrganizationsComputers for Organizations
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28. Computers for Organizations
Network servers
Users use the Internet as a means of connecting
even if away from the offices.
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29. Computers for Organizations
Mainframes
Used in large organizations
Handle thousands of users
Users access through a terminal
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31. Computers for Organizations
Minicomputers
Called midrange computers
Power between mainframe and desktop
Handle hundreds of users
Used in smaller organizations
Users access through a terminal
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32. Computers for Organizations
Supercomputers
The most powerful
computers made
Handle large and
complex calculations
Process trillions of
operations per
second
Found in research
organizations
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33. Computers in Society
More impact than any other invention
Changed work and leisure activities
Used by all demographic groups
Computers are important because:
Provide information to users
Information is critical to our society
Managing information is difficult
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34. Computers in Society
Impact of computers
Like the Impact of automobile
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35. Computers in Society
The benefits of using computers
As varied as users
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36. Computers in Society
Computers at home
Many homes have multiple computers
Computers are used for Communication
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37. Computers in Society
Computers at home
Computers are used for
Business
Entertainment
Schoolwork
Finances
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38. Computers in Society
Computers in education
Computer literacy required at all levels
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39. Computers in Society
Computers in small business
Makes businesses more profitable
Allows owners to manage
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40. Computers in Society
Computers in industry
Computers are
used to design
products
Assembly
lines are
automated
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41. Computers in Society
Computers in government
Necessary to track data for population
Police officers
Tax calculation and collection
Governments were the first computer users
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42. Computers in Society
Computers in health care
Revolutionized health care
New treatments possible
Scheduling of patients has improved
Delivery of medicine is safer
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43. Memory
Memory refers to the physical devices used to store programs
(sequences of instructions) or data (e.g. program state information)
on a temporary or permanent basis for use in a computer or
other digital electronic device.
Primary memory is used for the information in physical systems
which are fast (i.e. RAM), as a distinction from Secondary memory,
which are physical devices for program and data storage which are
slow to access but offer higher memory capacity. Primary memory
stored on secondary memory is called "virtual memory".
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44. The term "storage" is often (but not always) used in separate
computers of traditional secondary memory such as tape, magnetic
disks and optical discs (CD-ROM and DVD-ROM). The term
"memory" is often (but not always) associated with
addressable semiconductor memory, i.e. integrated
circuits consisting of silicon-based transistors, used for example
as primary memory but also other purposes in computers and
other digital electronic devices.
There are two main types of semiconductor
memory: volatile and non-volatile. Examples of non-volatile
memory are flash memory (sometimes used as secondary,
sometimes primary computer memory)
and ROM/PROM/EPROM/EEPROM memory (used
for firmware such as boot programs). Examples of volatile
memory are primary memory (typically dynamic RAM, DRAM),
and fast CPU cache memory (typically static RAM, SRAM, which
is fast but energy-consuming and offer lower memory capacity per
area unit than DRAM) .
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45. Classification of Memory
Memory
Volatile Non-Volatile
computer memory that requires
power to maintain the stored
information.
computer memory that can
retain the stored information
even when not powered.
•RAM
•DRAM (e.g., DDR SDRAM)
•SRAM
•Cache
•ROM
•PROM
•EPROM
•EEPROM
•Flash memory
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46. Full Form Type Function
RAM Read and Write
Memory
Volatile RAM is a form of data storage that can be
accessed randomly at any time, in any
order and from any physical location.
DRAM Dynamic RAM Volatile that stores each bit of data in a
separate capacitor within an integrated
circuit.
SRAM Static RAM Volatile Each bit in an SRAM is stored on
four transistors (M1, M2, M3, M4) that
form two cross-coupled inverters
CACHE Volatile Cache is a kind of RAM which a computer
system can access more responsively than
it can in regular RAM.
ROM Read only Memory Non-Volatile Read-only memory or ROM is also a form
of data storage that can not be easily
altered or reprogrammed.
PROM Programmable
read-only memory
Non-Volatile is a form of digital memory where the
setting of each bit is locked by
a fuse or antifuse.
EPROM Erasable
programmable read
only memory
Non-Volatile is a type of memory chip that retains its
data when its power supply is switched off
FLASH Non-Volatile which is intended to contribute to portable
storage and a convenient transfer of data
from one computer to another.
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