The document outlines the history of computers, detailing various eras from simple tools like the abacus through the mechanical and electro-mechanical periods to the present electronic era. It highlights key inventions, including the differential engine by Charles Babbage, Ada Lovelace as the first computer programmer, and the transition from vacuum tubes to transistors in computing. Additionally, it categorizes generations of computers and their characteristics, illustrating the rapid technological advancements that led to modern computing.

1. Computer history.
Thing that Changed the World

2. Computer history.
 Introduction
 The Eras of Computers
 First era [simple tools ]
 Second era [Mechanical
& Electro-mechanical Era (1623-1945)]
 Third era [Electronic Era (present)]
 Generations

3. Famous Quotes about Computers
 “I think there is a world market for
maybe five computers.” – Thomas
Watson, chairman of IBM, 1943
 “Computers in the future may weigh
no more than 1.5 tons.” – Popular
Mechanics, 1949
 “There is no reason anyone in the
right state of mind will want a
computer in their home.” – Ken
Olson, President of Digital Equipment
Corp, 1977.

4. Famous Quotes about Computers
 "So we went to Atari and said, 'Hey, we've
got this amazing thing, even built with
some of your parts, and what do you think
about funding us? Or we'll give it to you.
We just want to do it. Pay our salary, we'll
come work for you' And they said, 'No.' So
then we went to Hewlett-Packard, and they
said, 'Hey we don't need you. You haven't
got through college yet.'" - Apple Computer
Inc. founder Steve Jobs on attempts to get
Atari and HP interested in his and Steve
Wozniak's personal computer.

5. Who invented the computer ?
• It is not a question with a simple
answer. The real answer is that many
inventors contributed to the history of
computers and that a computer is a
complex piece of machinery made up of
many parts, each of which can be
considered a separate invention.

6. Introduction
The first computers were people
• Computers were given this name because
they performed the work that had
previously been assigned to people.
"Computer" was originally a job title.
• It was used to describe those human
beings (predominantly women) whose job
it was to perform the repetitive
calculations required to compute.

7. Introduction
• So imagine you had a job where hour
after hour, day after day, you were to do
nothing but compute multiplications.
Boredom would quickly set in, leading to
carelessness, leading to mistakes. And
even on your best days you wouldn't be
producing answers very fast. Therefore,
inventors have been searching for
hundreds of years for a way to
mechanize this task.

8. Introduction
• The earliest counting devices known
to man were his own hands and
fingers. If that wasn't enough ,
things in nature were used like
shells, stones.

9.  First era [simple tools ]
• Man's invention of the computer
resulted from man's need to
quantify ,to do mathematic
calculations ,man was inventing
easier and faster ways of
calculating.

10. First era [simple tools ]
• The most important One of this earlier
invention was The abacus .
• The abacus is a simple counting aid,
may have been invented in Babylonia
(now Iraq) in the fourth century B.C.
• Its only value is that it aids the memory
of the human performing the calculation.
• "calculus" comes from the Latin word for
pebble

11. A very old abacus

12. First era [simple tools ]
• The abacus is considered the first
personal calculator
• So we can say that Computers have
their beginnings back in pre-history,
starting with the abacus.
• A century later, the Arabs invented the
decimal numbering system — the basic
language of mathematics .

13. First era [simple tools ]
• Arabic numerals are introduced to Europe
in the 8 and 9 centuries A.D. Roman
numerals remain in use in some parts of
Europe until the 17 century. The Arabic
system introduced the concepts of the 0 and
fixed places for tens, hundreds, thousand,
etc., and greatly simplified mathematical
calculations.
• The model of the abacus integrated the
knowledge of the decimal number system
and evolved into a mechanical calculator.

14. • In the 17 century John Napier, invents
logs in 1614. Logs allow multiplication
and division to be reduced to addition
and subtraction.
• where the logarithm
values were carved on
ivory sticks which are
now called Napier's
Bones
An original set
of Napier's Bones
First era [simple tools ]

15. A more modern set of Napier's Bones

16. The Mechanical Era (1623-1945)
• Wilhelm Schickard builds the first
mechanical calculator in 1623. to
actually be built was probably the
calculating clock It can work with
six digits, and carries digits across
columns.

17. Schickard's Calculating Clock

18. Slide rule
 England in 1632
 NASA engineers of the Mercury,
Gemini, and Apollo programs
18

19. The Mechanical Era (1623-1945)
• In 1642 Blaise Pascal, at age 19, invented
the Pascaline as an aid for his father who
was a tax collector It used addition to
subtract, multiple and divide .
• Blaise Pascal builds a mechanical calculator.
It has the capacity for eight digits, but has
trouble carrying and its gears tend to jam.
• the odometer portion of a car's
speedometer
• Although this machine could perform addition
and subtraction on whole numbers, it was too
expensive and only Pascal himself could repair
it

21. A Pascaline opened up so you can observe the gears and
cylinders which rotated to display the numerical result

22. Stepped reckoner
 German Gottfried Wilhelm Leibniz (co-
inventor with Newton of calculus)
 addition, subtraction, multiplication,
and division
 fluted drums having ten flutes
arranged around their circumference in
a stair-step fashion
 first to advocate use of the binary
number system
22

23. The Mechanical Era (1623-1945)
• Joseph-Marie Jacquard invents
an automatic loom controlled by
punch cards.

24. The Mechanical Era (1623-1945)
How the automated loom machine work
• automated loom machine operated by
dropping needles through holes punched
in cards. When the needle passed
through the hole it lifted a weaving
thread, if the needle did not drop
through the hole the weaving thread
lowered. When the weaving shuttle
passed through the threads it developed
a pattern.

25. A close-up of a Jacquard card

26. automated loom machine
• Since the needles were up or down
like on or off switches used in
computers today the automated loom
is considered the “true digital
computer”.
• the punched card system later
applied to the U.S. census and then
to computers...

27. The Mechanical Era (1623-1945)
• By 1822 the English mathematician Charles
Babbage was proposing a steam driven
calculating machine the size of a room, which he
called the Difference Engine
• This machine would be able to compute tables of
numbers, such as logarithm tables
• Funded by British Government due to the
importance of numeric tables in ocean navigation
• Ten years later the device was still nowhere near
complete, acrimony abounded between all
involved, and funding dried up. The device was
never finished.

28. A small
section of the
type of
mechanism
employed in
Babbage's
Difference
Engine

29. The Mechanical Era (1623-1945)
• Babbage was not deterred, and by then was
on to his next brainstorm, which he called the
Analytic Engine. This device, large as a
house and powered by 6 steam engines
• Babbage who made an important
intellectual leap regarding the punched,
the presence or absence of each hole in the
card physically allows a colored thread to pass
or stops that thread cards In the Jacquard
loom,

30. The Mechanical Era (1623-1945)
• Babbage saw that the pattern of holes
could be used to represent an abstract
idea such as a problem statement or the
raw data required for that problem's
solution.
• The Analytic Engine also had a key
function that distinguishes computers
from calculators (conditional statement)
• Furthermore, Babbage realized that
punched paper could be employed as a
storage mechanism, holding computed
numbers for future reference

31. The Mechanical Era (1623-1945)
 Ada Byron Though she was only 19, she was
fascinated by Babbage's ideas and through
letters and meetings with Babbage she learned
enough about the design of the Analytic Engine
to begin fashioning programs for the still
unbuilt machine
 Ada wrote a series of "Notes" wherein she
detailed sequences of instructions she had
prepared for the Analytic Engine

32. The Mechanical Era (1623-1945)
 But Ada earned her spot in history
as the first computer programmer.
Ada invented the subroutine and
was the first to recognize the
importance of looping .

33. 33

34. The Mechanical Era (1623-1945)
• Hollerith's invention, known as the
Hollerith desk (1890) consisted of
a card reader which sensed the
holes in the cards .
 read census information which had
been punched onto card
 reading errors were consequently
greatly reduced
 work flow was increased

35. A few Hollerith desks still exist today

36. The Mechanical Era (1623-1945)
• The patterns on Jacquard's cards were
determined when a tapestry was designed and
then were not changed. Today, we would call
this a read-only form of information storage.
Hollerith had the insight to convert punched
cards to what is today called a read/write
technology.
• Hollerith's technique was successful and the
1890 census was completed in only 3 years at a
savings of 5 million dollars.

37. The Mechanical Era (1623-1945)
• Hollerith built a company, the
Tabulating Machine Company which,
after a few buyouts, eventually
became International Business
Machines, known today as IBM.
• IBM grew rapidly and punched cards
became ubiquitous .

38. The end of the Mechanical Era
• As physics paved the way for electrical
innovation, scientists discovered in electrical
charge a way to represent data. The beads of
the abacus were replaced by bits in the modern
computer – essentially a bit or ‘binary digit’ is a
small electrical charge that represents a 1 or 0.
The creation of the bit marked a transition from
the decimal system for humans (10 primary
numbers from zero to nine) to a binary system
for computers (only two numbers, 0 and 1).

39. Electro-Mechanical Era (1920 - 1945)
• For the first time electricity was used in
the operation of computers, but
computers still had many mechanical
components.
• Programming a computer did not
involve software. Rather, the
programmer actually rewired the paths
of electricity through the machine in
order to change its mode of operation

40. Z3
 In 1941, Konrad Zuse
 the first operational, general-purpose,
programmable (that is, software
controlled) digital computer designed
to solve complex engineering
equations
 the first machine to work on the binary
system
 a hole (1) or no hole (0)
 2 to the power of the number of bits in
the binary number
40

41. 41

42. Third era [Electronic Era (present)]
• This era development is often referred
to in reference to the different
generations of computing devices. Each
generation of computer is characterized
by a major technological development
that fundamentally changed the way
computers operate, resulting in
increasingly smaller, cheaper, more
powerful and more efficient and reliable
devices.

43. Mark I
 In 1944, Howard Aiken, in
collaboration with engineers at IBM
 the first programmable digital
computer
 constructed out of switches, relays,
rotating shafts, and clutches
 handled 23-decimal-place numbers
 special built-in programs, or
subroutines, to handle logarithms
and trigonometric functions 43

44. Mark I
 weighed 5 tons, incorporated 500
miles of wire, was 8 feet tall and 51
feet long, and had a 50 ft rotating
shaft running its length, turned by a
5 horsepower electric motor
 A paper tape instead of punched
cards
 Mark I ran non-stop for 15 years
44

45. 45

46. Computer Bug
 Grace Hopper
 a dead moth that had gotten into
the Mark I
 wings were blocking the reading of
the holes
 the first high-level language, "Flow-
matic“ in 1953 became COBOL
 a compiler
46

47. Turing machine
 British mathematician Alan Turing in
1936
 perform logical operations and could
read, write, or erase symbols
written on squares of an infinite
paper tape
 a finite state machine
 a state diagram - visual path of the
possible states that the machine
can enter, dependent upon the 47

48. 48

49. Integrated Circuits
 The microelectronics revolution
 a small sliver of silicon
 millions of transistors can be
created and interconnected
 IBM Stretch computer of 1959 -
150,000 transistors
 individual elements requiring
individual assembly
49

50. ENIAC
 Electronic Numerical Integrator and
Calculator
 University of Pennsylvania between
1943 and 1945
 John Mauchly and J. Presper
Eckert
 "I was astounded that it took all this
equipment to multiply 5 by 1000“
 weighed 30 tons, more than 18,000
vacuum tubes 50

51. ENIAC
 silent but generated waste heat
 solved the tube reliability problem
through extremely careful circuit
design
 hold 20 numbers at a time
 ran much faster than the Mark I
 first ENIAC program - declared the
hydrogen bomb feasible
51

52. 52

53. EDVAC
 John von Neumann - pioneered
the stored program in 1945
 a simple, fixed structure
 to execute any kind of computation
 without the need for hardware
modification
 worked out the complicated method
needed to detonate an atomic bomb
53

54. 54

55. Computer Generations
• (Zero Generation -1920's Electro-mechanical)
• First Generation - 1946-1956: Vacuum Tubes
• Second Generation - 1956-1963: Transistors
• Third Generation - 1964-1971: Integrated Circuits
• Fourth Generation - 1971-Present:
Microprocessors
• Fifth Generation - Present and Beyond: Artificial
Intelligence

56. First Generation of Computers:
1946 - 1956
 Vacuum Tubes
 Punch Cards
 The UNIVAC

57. The size of a cell phone built with
Vacuum Tubes

58. The size of a pager built with vacuum
tubes

59. The size of a home computer built with
vacuum tubes

60. Punch Cards
 At the time, the primary way to enter
information and programs into a
computer

61. The UNIVAC
 Built in 1951 by Remington Rand
 The first computer mass produced
for general use
 Used magnetic tape instead of
punch cards for input and output

62. Electronic Computer Generation
 They relied on vacuum tubes to store and
process information.
 They consumed a great deal of power,
were short lived and generated a great
deal of heat.
 They used magnetic drum memories.

63.  Maximum memory size was aproxim.
2000bytes
With a speed of 10 kilo instructions per sec.
 EDVAC (Electronic Discrete Variable
Automatic Computer) was the 1st
computer
(Based on Von Nuemann architecture) to
use instructions stored in memory.
 1st
Generation Computers included the
UniVersal Automatic Computer (UNIVAC)
and IBM 650.

64. Second Generation of Computers:
1957 - 1963
 Transistors
 Admiral Grace Hopper

65. Transistors
 The transistor (on/off switch) was invented in
1948 and began to replace vacuum tubes in
computers by 1956.
 Developed by a team at Bell Labs, won the
Nobel Prize in Physics in 1956.
 Transistors allowed computers to become
smaller, faster and more reliable.
 Today, transistors are about .25 microns in
size, that is smaller than the width of a human
hair.

66. The First Transistor

67. Grace Hopper revolutionizes
computer programming
 Rear Admiral Grace Hopper
 Born December 9, 1906 in New York City
 One of the first US computer
programmers
 A leader in the field of compilers
 Believed that programming languages should
be more like English
 Was a leading force in the development of
the COBOL business programming
language
 Coined the term “Debugging”

68. 2ND
Generation :1957 - 1963
 They relied on transistor technology and
magnetic core memories .
 Computer were then built from individual
transistors wired-up together .
 Transistors were much more stable and
reliable than vacuum tube, they
generated less heat and consumed less
power.
 Memory size expanded to 32KB of RAM
 Speeds reached 200000 to 300000
instructions per sec.eg
IBM7094,NCR501.

69. Third Generation of Computers:
1964 - 1979
 The rise of operating systems,
minicomputers, and word
processing
 Integrated Circuits
 IBM 360
 PDP-8
 Development of the first computer
networks

70. Integrated Circuits
 Integrated circuits (computer chips)
began replacing transistors
 An integrated circuit contains many
transistors and electronic circuits on
a single wafer of silicon or chip.

71. The IBM 360
 Developed in 1964, the first
computer to use integrated circuits.
 Became the basic model for other
mainframes produced by IBM and
other companies.
 Price: Up to a million dollars
 Number sold: 14,000 by 1968

72. The IBM 360

73. The PDP-8
 The first microcomputer, produced
by Digital Equipment Co. (DEC) in
1965.
 Cost: $5,000
 Number Sold: 50,000

74. The PDP-8

75. 3rd
Generation :1964 – 1979
 Used Integrated Circuits (IC) which were made
by combining several transistors together.
 Magnetic disk was developed during this period
for storage purposes.
 Computer memories expanded to 2MB RAM and
speeds up to 5million instructions per sec.
 This period saw the production of First
microcomputer(1974).
 3rd
Generation consisted of fast mainframe
computers e.g IBM 360,370 and 8-bit
microcomputers.

76. Fourth Generation of Computers: 1979
- Present
 The Microprocessor
 The First Microcomputers

77. The Microprocessor
 A computer chip that
contains on it the
entire CPU
 Mass produced at a
very low price
 Computers become
smaller and cheaper
 Intel 4004 – the first
computer on a chip,
more powerful than
the original ENIAC.

78. The Microcomputer
 1975 - The first microcomputer, the
Altair 8800 was introduced. The
BASIC translator used by the Altair
was developed by Bill Gates
 1975 – The first super computer,
the Cray –1, was announced
 1976 – DEC introduces its
minicomputer, the VAX

79. The Microcomputer
 1977 – Steve Jobs and Steve
Wozniak begin producing Apple
computers in a garage
 1978 – The first spreadsheet for
Apple is introduced
 1981 – IBM introduces the IBM
Personal Computer. Uses the MS-
DOS operating system (birth of
Microsoft)
 By 1982, 835,000 IBM PCs had been sold

80. The Microcomputer
 1982 – Sun Microsystems
introduces its first workstation
 1984 – Apple produces the first
Macintosh
 1985 – Microsoft introduces
Windows

81. Summary
Generation 1st
Generation
2nd
Generation
3rd
Generation
4th
Generation
Technology Vacuum
Tubes
Transistors
Integrated
Circuits
Microchips
Size Filled a
room
Filled half
a room
Smaller
Tiny, palm
top

82. 4th
Generation:1979 - 1989
 They used Large scale integration(LSI – which
combined hundreds of transistors) and Very
Large Scale Integration (VLSI-which combines
200000 to 400000 transistors) circuits.
 Memories used include magnetic disks, bubble
memories and optical disks.
 Memory sizes expanded to several hundred
megabytes and speeds to 50 million instructions
per sec.
 They included mainframes such as IBM 308 as
well as the 16-bit and 32-bit microcomputers.

83. 5th
Generation :1990-Present
 The Major thrust of Fifth generation of computers
are distributed computing systems and the
merging of telecommunications and computing
technology.
 Technologies currently used and under research
during this generation, include parallel
architectures, three dimensional circuit design
and super conducting materials.
 The above technologies have led to development
of supercomputers with speeds of 1G to 1T
instructions per sec.

84. The Future of Computing
 Bleeding Edge Technology
 Molecular Computing
 DNA Computing
 Biological Computing
 Quantum Computing

85. Molecular Computing
 The amount of circuitry that can be
placed on a silicon chip is limited.
 As more transistors are crammed onto a
silicon chip the process becomes complex
and expensive.
 Today about 28 million transistors can be
placed on a computer chip.
 Molecules are much smaller than
transistors.
 Molecular chips that contain billions or
trillions of switches and components.

86. Advantages of Molecular
Computing
 Main Advantages
 Potential to pack vastly more circuitry
onto a microchip than will ever be
possible with silicon chips
 Astonishing fast
 Potentially cheap and easy to produce

87. Potential Uses of Molecular
Computing
 Potential Uses
 Molecular memories with a million
times the storage of today’s chips
 Supercomputers the size of a wrist
watch
 Current Work
 Creating switches using molecules
 Molecules do not usually carry a current
 Small molecular devices that could be
integrated with today’s silicon chips

88. DNA Computing
 DNA is a unique data structure
 Has enormous data density – up to 1
million Gbits of data per inch
 Today’s best hard drive store about
7Gbits psi
 Double stranded nature has potential
for error correction
 Massively Parallel Operations
 Using enzymes, which operate on one
DNA at the same time

89. DNA Computing
 Main Advantages
 Massively parallel operations
 Huge memory capacity
 Possible Uses
 Solving computational problems that
can never be solved using silicon-based
computers.

90. Biological Computing
 Creating devices out of cells that
can compute and be programmed
 Probably not a replacement for
traditional computers
 Biological computing is at the stage
that traditional computing was in
the 1920s.

91. Biological Computing
 Possible Uses
 Process control for biochemical systems
 Insulin delivery systems that could
sense the amount of glucose in the
blood and deliver the right amount
 Devices that detect food contamination
or toxins in the air

92. Quantum Computing
 Computers based on quantum
mechanics
 Building block of data is the quantum
bit (or qubit)
 A qubit can exist in two states at the
same time, so it can hold a value of both
one and zero simultaneously
 Potential for parallel computation
 Disadvantages
 Fragile and difficult to control
 The whole system can lose coherence
and collapse.

93. Computer is a group of electronic devices used to
process the data.
The characteristics of a computer are:
4. Accuracy
5. Automation
6. Functionality
7. Tirelessness
1. Speed
2. Reliability
3. Memory capacity

94. 1.Speed: computer process the data at an
unimaginable speed. The speed of the computer
ranges up to Nano seconds.
2. Reliability: The next important characteristic of a
computer is its reliability. we can always rely on the
information given by a computer.
3. Memory capacity: The memory capacity of a
computer is measured in in bits and bytes. Large
amount of the data can be stored in computer and
retrieved. Memory capacity of the computer ranges
in Giga bytes.

95. 4. Accuracy: Accuracy of the computer is very
high it performs calculation with greater accuracy
in less time.
5. Automation: a computer allows automation
for any process designed in the from of a
program. A program can be executed any number
of times to repeat the process.

96. 6. Functionality: computer can performs many kinds
of jobs. They not process the data but also can be
Used for plying music, movies, and printing jobs.
It finds its applications in all most all the fields.
7. Tirelessness: A computer never gate tired.