1. Introduction to Computers
by
1

2. What Is A Computer?
A computer is an electronic device,
operating under the control of instructions
(software) stored in its own memory unit,
that can accept data (input), manipulate
data (process), and produce information
(output) from the processing.
Computer comes form the word compute
Commonly Operated Machine Particularly
Used for Training Education and Research
2

3. Flow Diagram
Central Processing Unit
Control Output
Input
Unit Device
Device
Memory
ALU
Unit
3

4. Characteristics
Versatility Diligence
Accuracy No Feelings
Power of remembering
Speed
No IQ
Common data used
Storage 4

5. Evolution of Computers
5

6. History of Computers - Long,
Long Ago
beads on rods to count and calculate
still widely used in Asia!
6

7. History of Computers - Way
Back When
Slide Rule 1630
based on Napier’s
rules for logarithms
used until 1970s
7

8. History of Computers - 19th
Century
first stored program -
metal cards
first computer
manufacturing
still in use today!
8

9. Charles Babbage - 1792-1871
Difference Engine c.1822
huge calculator, never
finished
Analytical Engine 1833
could store numbers
calculating “mill” used
punched metal cards for
instructions
powered by steam!
accurate to six decimal places 9

10. Evolution of Microprocessor
In the mid-1940s, John Von Neumann
invented a machine in storing programs
and calculations.
The last 20 years has seen a rapid
development of the smallest computers,
which is so called – Microcomputers.
This IC computer was designed by Hoff
and Stanley Mazor.
10

11. Evolution of Microprocessor
The MOS design of a 4004 4-bit chip
called- Microprocessor in 1971.
This chip is the heart of the computer
system, commonly referred as CPU
(Central processing unit).
The latest generation Intel pentium
processor have a speed up to 200 MHz.
11

12. The First Microprocessor – 1971
The 4004 had 2,250
transistors
four-bit chunks (four
1’s or 0’s)
108Khz
Called “Microchip”
12

13. Computer Generations
13

14. First Generations
1. VACUUM TUBES: 1942-1955
ENIAC Electronic Numerical Integrator And Calculator
1946, JP Eckert and JW Mauchly
EDVAC Electronic Discrete Variable Automatic Computer
Dr.John Von Neumann
EDSAC Electronic Delay Storage Automatic Calculator
1949, Professor Maurica Wilkes
VACUUM
TUBES:
1942-1955
14

15. Vacuum Tubes - 1942 - 1955
First Generation Electronic
Computers used Vacuum
Tubes
Vacuum tubes are glass tubes
with circuits inside.
Vacuum tubes have no air
inside of them, which protects
the circuitry.
15

16. First Generations
1. VACUUM TUBES: 1942-1955
Manchester Mark I
Professor MHA Newmann
UNIVAC Universal Automatic Computer
1951 . UNIVAC I in 1952 by IBM. UNIVAC II in 1954 by GEC
VACUUM
TUBES:
1942-1955
16

17. UNIVAC - 1951
first fully electronic
digital computer built in
the U.S.
Created at the University
of Pennsylvania
ENIAC weighed 30 tons
contained 18,000 vacuum
tubes
Cost a paltry $487,000
17

18. Grace Hopper
Programmed UNIVAC
Recipient of Computer
Science’s first “Man of
the Year Award
Award”
18

19. First Computer Bug - 1945
Relay switches
part of computers
Grace Hopper
found a moth
stuck in a relay
responsible for a
malfunction
Called it
“debugging” a
computer
19

20. Second Generations
2. TRANSISTORS: 1955-1964
Uses Silicon First Transistor
developed in 1948
won a Nobel prize
on-off switch
Second Generation
Computers used Transistors,
starting in 1956
VACUUM TUBES: TRANSISTORS: 1955-
1942-1955 1964
20

21. Third Generations
3. INTEGRATED CIRCUITS: 1964-1975
IBM 360 1964
ALO
Mini computers
ECIL- TDC 316 , 332
VACUUM TUBES: TRANSISTORS: 1955- IC
1942-1955 1964 1964-1975
21

22. Third Generation – 1964-1971
1964-1971
Integrated Circuit
Operating System
Getting smaller, cheaper
22

23. What is a Microchip?
Very Large Scale Integrated Circuit
(VLSIC)
Transistors, resistors, and capacitors
4004 had 2,250 transistors
Pentium IV has 42 MILLION transistors
Each transistor 0.13 microns (10-6 meters)
23

24. Fourth Generations
4. VERY LARGE-SCALE INTEGRATED (VLSI) CIRCUITS:
1975 onwards
Large Integration
Portable
Minimum maintenance on Hardware
Heat generated is negligible
No AC is required
Much faster
VACUUM TUBES: TRANSISTORS: 1955- IC VLSI
1942-1955 1964 1964-1975 1975
24

25. Birth of Personal Computers - 1975
256 byte memory
(not Kilobytes or
Megabytes)
2 MHz Intel 8080
chips
Just a box with
flashing lights
cost $395 kit, $495
assembled.
25

26. IBM PC - 1981
IBM-Intel-Microsoft joint venture
First wide-selling personal
computer used in business
8088 Microchip - 29,000
transistors
4.77 Mhz processing speed
256 K RAM (Random Access
Memory) standard
One or two floppy disk drives
26

27. Apple Computers
Founded 1977
Apple II released 1977
widely used in schools
Macintosh (left)
released in 1984, Motorola
68000 Microchip processor
first commercial computer with
graphical user interface (GUI)
and pointing device (mouse)
27

28. Computers Progress
UNIVAC Mits IBM PC Macintosh Pentium
(1951-1970) Altair (1981) (1984) IV
(1968 vers.)
(1975)
Circuits Integrated 2 Intel Intel 8088 Motorola Intel P-IV
Circuits 8080 Microchip 68000 Microchip
Microchip - 29,000
Transistors
- 7.5 million
transistors
RAM 512 K 265 Bytes 256 KB 256 MB
Memory
Speed 1.3 MHz 2 KHz 4.77 MHz 3200 MHz
= 3.2 GHz
Storage 100 MB 8” Floppy Floppy Floppy Hard
Hard Drive Drive Drive Drives Drive,
Floppy,
CD-Rom
Size Whole Briefcase Briefcase Two Small
Room (no monitor) + Monitor shoeboxes Tower
(integrated
monitor)
Cost $1.6 million $750 $1595 ~$4000 $1000 -
$2000
28

29. 1990s: Pentiums and Power
Macs
Early 1990s began penetration of computers into
every niche: every desk, most homes, etc.
Faster, less expensive computers paved way for
this
Windows 95 was first decent GUI for “PCs”
Macs became more PC compatible - easy file
transfers
29

30. Fifth Generations
5. Ultra LARGE-SCALE INTEGRATED (USLI) 1991
Microprocessor based
PROLOG may be used
Multimedia, KBS
Basic, Fortran, COBOL
KIPS, DIPS/LIPS
AI
VACUUM TUBES: TRANSISTORS: 1955- IC VLSI USLI
1942-1955 1964 1964-1975 1975 1991
30

31. Basic Components
Hardware
Software
Peripherals
Basic Operations
Inputting
Storing
Processing
Outputting
Controlling 31

32. What Are The Primary
Components Of A Computer ?
Input devices.
Central Processing
Unit (containing the
control unit and the
arithmetic/logic
unit).
Memory.
Output devices.
Storage devices.
Power Supply Unit
Motherboard
32

33. Devices that comprise a computer system
Monitor Speaker
(output) (output) System unit
(processor, memory…)
Printer
(output)
Storage devices
(CD-RW, Floppy,
Hard disk, zip,…)
Mouse
(input)
Scanner Keyboard
(input)
(input)
33

34. Input Devices
Keyboard.
Punch Card
Paper tape
Mouse.
Light pen
Touch screen
MICR (Magnetic Ink Character Recognition)
Bar Code Reader
OCR (Optical Character Recognition)
34

35. The Keyboard
The most commonly used input device is the
keyboard on which data is entered by manually
keying in or typing certain keys. A keyboard
typically has 101 or 105 keys.
35

36. The Mouse
Is a pointing device which is used to control the
movement of a mouse pointer on the screen to
make selections from the screen. A mouse has one
to five buttons. The bottom of the mouse is flat
and contains a mechanism that detects movement
of the mouse.
36

37. The Central processing Unit
The central processing unit (CPU) contains
electronic circuits that cause processing to occur.
The CPU interprets instructions to the computer,
performs the logical and arithmetic processing
operations, and causes the input and output
operations to occur. It is considered the “brain”
of the computer.
37

38. Memory
Memory also called Random Access Memory or
RAM (temporary memory) is the main memory of
the computer. It consists of electronic
components that store data including numbers,
letters of the alphabet, graphics and sound. Any
information stored in RAM is lost when the
computer is turned off.
Read Only Memory or ROM is
memory that is etched on a chip
that has start-up directions for
your computer. It is permanent
memory. 38

39. Amount Of RAM In Computers
The amount of memory in SIMM
computers is typically measured
in kilobytes or megabytes. One
kilobyte (K or KB) equals
approximately 1,000 memory DIMM
locations and one megabyte (M
or MB) equals approximately one
million locations A memory
location, or byte, usually stores
one character.
SODIMM
Therefore, a computer with 8 MB
of memory can store
approximately 8 million
characters. One megabyte can
hold approximately 500 pages of
text information.
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40. What Does A Computer Do?
Computers can perform four
general operations, which
comprise the information
processing cycle.
Input
Process
Output
Storage
40

41. Storage Devices
Auxiliary storage devices are used to
store data when they are not being
used in memory. The most common
types of auxiliary storage used on
personal computers are floppy disks,
hard disks and CD-ROM drives.
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42. Floppy Disks
A floppy disk is a
portable, inexpensive
storage medium that
consists of a thin,
circular, flexible plastic
disk with a magnetic
coating enclosed in a
square-shaped plastic
shell.
42

43. Structure Of Floppy Disks
A folly disk is a magnetic disk, which means
that it used magnetic patterns to store data.
Data in floppy disks can be read from and
written to.
Formatting is the process of preparing a
disk for reading and writing.
A track is a narrow recording band that forms
a full circle on the surface of the disk.
43

44. Structure Of Floppy Disks
The disk’s storage locations are divided into pie-
shaped sections called sectors.
A sectors is capable of holding 512 bytes of data.
A typical floppy stores data on both sides and has 80
tracks on each side with 18 sectors per track.
44

45. Hard Disks
A hard disk consists of one or more rigid
metal plates coated with a metal oxide
material that allows data to be magnetically
recorded on the surface of the platters.
The hard disk platters spin at a high rate of
speed, typically 5400 to 7200 revolutions per
minute (RPM).
Storage capacites of hard disks for personal
computers range from 10 GB to 120 GB (one
billion bytes are called a gigabyte).
45

46. Compact Discs
A compact disk (CD), also called an optical disc, is a
flat round, portable storage medium that is usually
4.75 inch in diameter.
A CD-ROM (read only memory), is a compact disc
that used the same laser technology as audio CDs for
recording music. In addition it can contain other
types of data such as text, graphics, and video.
The capacity of a CD-ROM is 650 MB of data.
46

47. Output Devices
Output devices make the information
resulting from the processing available for
use. The two output devices more commonly
used are the printer and the computer
screen.
The printer produces a
hard copy of your
output, and the
computer screen
produces a soft copy of
your output. 47

48. Output devices
• Convert from electronic form to some other form
• May display the processed results
• Usable information
Monitor or screen Printer
Text Black and white
Numbers Color
Symbols
Art
Photographs
Video
48

49. Motherboard
Contains built-in electronic
components
All components like
keyboard, mouse, printers
and disk drives are
attached.
49

50. Motherboard
Intel
AMD Atholon
50

51. Power Supply Unit
The power supply is one of the
most important parts that needs to
be understood. The power supply
unit provides electrical power for
every component inside the
system unit.
The power supply plays the
critical role of converting
commercial electrical power (AC),
into DC required by the
components of the computer.
51

52. Power Supply Unit
There are two basic types of
power supplies:
AT power supplies –
Designed to support AT-
compatible motherboards.
ATX power supplies –
Designed according to
newer ATX design
specifications to support the
ATX motherboard. 52

53. Printers
Impact Printer.- DOT matrix, Daisy
Wheel, Line
Non – Impact Printer – Laser, Ink jet
COM (Computer output to microfilm)
53

54. Data and Information
All computer processing requires data, which is a
collection of raw facts, figures and symbols, such as
numbers, words, images, video and sound, given to
the computer during the input phase.
Computers manipulate data to create information.
Information is data that is organized, meaningful,
and useful.
During the output Phase, the information that has
been created is put into some form, such as a printed
report.
The information can also be put in computer storage
for future use. 54

55. Why Is A Computer So Powerful?
The ability to perform the information
processing cycle with amazing speed.
Reliability (low failure rate).
Accuracy.
Ability to store huge amounts of data
and information.
Ability to communicate with other
computers.
55

56. How Does a Computer
Know what to do?
It must be given a detailed list of instructions,
called a compute program or software,
that tells it exactly what to do.
Before processing a specific job, the
computer program corresponding to that job
must be stored in memory.
Once the program is stored in memory the
compute can start the operation by executing
the program instructions one after the other.
* 56

57. Computer Applications
Computer Assisted Instructions (CAI).
Computer Assisted Learning (CAL).
Computer Aided Learning & Teaching
Medical
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