The evolution of the modern-day computer started inThe evolution of the modern-day computer started in ChinaChina
at aroundat around 500 BC500 BC. The abacus was probably the original. The abacus was probably the original
counting device. It has survived centuries of technologicalcounting device. It has survived centuries of technological
advancement for its widely used today.advancement for its widely used today.
The Abacus are the earliestThe Abacus are the earliest
known counting/calculationknown counting/calculation
Used to aid mentalUsed to aid mental
3000 BC: The3000 BC: The abacusabacus isis
invented in Babyloniainvented in Babylonia
Used by Greeks and RomansUsed by Greeks and Romans
Refined to suit countingRefined to suit counting
system of each culturesystem of each culture
Abacus were also developedAbacus were also developed
by Native American culturesby Native American cultures
John NapierJohn Napier, a Scottish theologian and mathematicians,, a Scottish theologian and mathematicians,
became famous for his discovery of logarithms. He inventedbecame famous for his discovery of logarithms. He invented
inin 16171617 the device that could do this – the Napier’s bone – athe device that could do this – the Napier’s bone – a
table of logarithms made of ivory.table of logarithms made of ivory.
William Oughtred, an English
mathematician, invented the
SLIDE RULE, a device made
of wood with movable scales
arrange to slide opposite each
InIn 16421642, a French, a French
mathematician namedmathematician named BlaiseBlaise
PascalPascal invented and built theinvented and built the
Pascaline. His invention usedPascaline. His invention used
gear-driven counting wheelsgear-driven counting wheels
to do addition. He inventedto do addition. He invented
this device to help his fatherthis device to help his father
who was a tax collector. Awho was a tax collector. A
programming language wasprogramming language was
later named after the him –later named after the him –
Pascal ProgrammingPascal Programming
Gottfried Wilhelm von Leibniz, a German mathematician. His
machine, the LEIBNIZ MACHINE, considered of a stepped
cylinder that could perform the four fundamental operations an
InIn 18011801, a French named, a French named
Joseph-Marie JacquardJoseph-Marie Jacquard
invented a weaving loom thatinvented a weaving loom that
was aptly called Jacquardwas aptly called Jacquard
Weaving Loom. This device,Weaving Loom. This device,
which still used at present, iswhich still used at present, is
controlled by cards in whichcontrolled by cards in which
holes are strategically punched.holes are strategically punched.
The punched cards areThe punched cards are
sequenced to indicate asequenced to indicate a
particular weaving device.particular weaving device.
The concepts used in modern-day computers were laid downThe concepts used in modern-day computers were laid down
by the nineteenth century English visionary and Cambridgeby the nineteenth century English visionary and Cambridge
professorprofessor Charles BabbageCharles Babbage. He invented the Difference. He invented the Difference
Engine inEngine in 18221822, which was capable of computing, which was capable of computing
mathematical tables and polynomial equations.mathematical tables and polynomial equations.
Charles Babbage is known to be the “Father of
1833 – Charles Babbage also invented the
ANALYTICAL MACHINE designed to perform
complex mathematical calculations. This was
considered to be the first general purpose
Charles Babbage: Difference Engine &Charles Babbage: Difference Engine &
Analytical EngineAnalytical Engine
In 1822, Babbage proposed building a machine called theIn 1822, Babbage proposed building a machine called the
Difference EngineDifference Engine to automatically calculate mathematicalto automatically calculate mathematical
tables. The Difference Engine was only partially completedtables. The Difference Engine was only partially completed
when Babbage conceived the idea of another, morewhen Babbage conceived the idea of another, more
sophisticated machine called ansophisticated machine called an Analytical Engine.Analytical Engine.
The Analytical Engine was intended to use loops ofThe Analytical Engine was intended to use loops of
Jacquard's punched cardsJacquard's punched cards to control an automaticto control an automatic
calculator, which could make decisions based on thecalculator, which could make decisions based on the
results of previous computations.results of previous computations.
The Analytical Machine was designed to be stream -drivenThe Analytical Machine was designed to be stream -driven
and fully automatic rather than requiring the user toand fully automatic rather than requiring the user to
mechanically input all the data as did the Differencemechanically input all the data as did the Difference
Neither machine was finished because Babbage keptNeither machine was finished because Babbage kept
updating his design.updating his design.
Babbage’s ConditionalBabbage’s Conditional
The Analytical Machine was also intended to employThe Analytical Machine was also intended to employ
several features subsequently used in modern computers,several features subsequently used in modern computers,
including sequential control, branching, and looping.including sequential control, branching, and looping.
The conditional decision meant that the path a calculationThe conditional decision meant that the path a calculation
would follow could be altered depending on the answer towould follow could be altered depending on the answer to
the previous step in the calculation.the previous step in the calculation.
The use of a card system to ‘store’ a program and theThe use of a card system to ‘store’ a program and the
development of the conditional state were significantdevelopment of the conditional state were significant
contributions to the future of computingcontributions to the future of computing
Augusta Ada Lovelace (LordAugusta Ada Lovelace (Lord
Byron’s daughter) worked withByron’s daughter) worked with
Babbage and created a programBabbage and created a program
for the Analytical Machine. She isfor the Analytical Machine. She is
considered to be the firstconsidered to be the first
Herman Hollerith, an
and founder of
Company (now called
Machine or IBM)
invented the CENSUS
The US government facedThe US government faced
a dilemma because usinga dilemma because using
the existing systemthe existing system
collatingcollating census datacensus data byby
making tally marks inmaking tally marks in
small squares on rolls ofsmall squares on rolls of
paper and then adding thepaper and then adding the
marks together by handmarks together by hand
was extremely timewas extremely time
If the system remainedIf the system remained
unchanged, the data fromunchanged, the data from
the 1890 census wouldthe 1890 census would
not be collated into anynot be collated into any
useful form until well afteruseful form until well after
the 1900 census.the 1900 census.
Herman Hollerith’s Tabulating MachineHerman Hollerith’s Tabulating Machine
The Birth of IBMThe Birth of IBM
(International Business Machines)(International Business Machines)
Hollerith’s system proved to beHollerith’s system proved to be
both useful and efficient.both useful and efficient.
It was only useful forIt was only useful for
tabulation not for directtabulation not for direct
complex computation.complex computation.
Not a ‘real’ computerNot a ‘real’ computer
The use of perforated orThe use of perforated or
punched cards for datapunched cards for data
entry was a major usefulentry was a major useful
In February 1924, Hollerith'sIn February 1924, Hollerith's
company changed its namecompany changed its name
toto International BusinessInternational Business
MachinesMachines, or, or IBMIBM..
Punched Cards & TapePunched Cards & Tape
The original cards had round holes (45 per row by 1900).The original cards had round holes (45 per row by 1900).
The use of punched cards (and paper tape) for computerThe use of punched cards (and paper tape) for computer
input lasted for many yearsinput lasted for many years
Later cards (about 1929 onwards) used rectangularLater cards (about 1929 onwards) used rectangular
cards and had 80 holes per row. (This is the type ofcards and had 80 holes per row. (This is the type of
computer card you may have seen since they werecomputer card you may have seen since they were
around for a long time.)around for a long time.)
William Seward Burroughs, an American inventor, designed
a key-driven machine that produced a hardcopy. This was
called ADDING/CALCULATING MACHINE.
Dr. John AtanasoffDr. John Atanasoff and his assistantand his assistant Clifford BerryClifford Berry design anddesign and
began to build the first electronic computer during the winterbegan to build the first electronic computer during the winter
ofof 1937-381937-38. Their machine, the Atanasoff-Berry Computer or. Their machine, the Atanasoff-Berry Computer or
ABC provided the foundation for the next advances inABC provided the foundation for the next advances in
electronic digital computers.electronic digital computers.
InIn 19441944,, IBMIBM sponsored the building of the firstsponsored the building of the first
electromechanical computer called theelectromechanical computer called the Mark IMark I. The credit for. The credit for
the creation of this goes tothe creation of this goes to Howard AikenHoward Aiken, a professor at, a professor at
Harvard University.Harvard University.
During the yearsDuring the years 1943 to 19461943 to 1946,, Dr. John W. MauchlyDr. John W. Mauchly andand J.J.
Presper Eckert Jr.Presper Eckert Jr. completed the ENIAC (Electroniccompleted the ENIAC (Electronic
Numerical Integrator and Calculator), the first large scaleNumerical Integrator and Calculator), the first large scale
electronic digital computer.electronic digital computer.
ENIAC had the capacity of 5,000
computations per second
Was developed by [USA]Was developed by [USA]
Army Ordnance toArmy Ordnance to
compute World War IIcompute World War II
ballistic firing tables.ballistic firing tables.
Early electronic digitalEarly electronic digital
1,800 Vacuum tubes1,800 Vacuum tubes
ENIAC could discriminateENIAC could discriminate
the sign of a number,the sign of a number,
compare quantities forcompare quantities for
equality, add, subtract,equality, add, subtract,
multiply, divide, andmultiply, divide, and
extract square roots.extract square roots.
ENIAC stored aENIAC stored a
maximum of twenty 10-maximum of twenty 10-
digit decimal numbers.digit decimal numbers.
Awesome in size
Controlled by thousands of vacuum tubes or valves
Consumes great amount of power that often
resulted in overheating and failure
The operators cannot recognize whether the
breakdown was in the programming or in the
Information were stored on punched cards as well
as on magnetic tapes
The language level used was machine language
which used numbers
During the firstDuring the first
generation, computersgeneration, computers
were built withwere built with vacuumvacuum
tubestubes – electronic tubes– electronic tubes
that were made of glassthat were made of glass
and were about the sizeand were about the size
of the light bulbs.of the light bulbs.
Transistors replaced vacuum tubes (used
less power and did not get so hot quickly)
Development of assembly or symbolic
Development of high level language such as
Fortran and Cobol allowed programmers
to give more attention to solving problems
This generation began with the with the firstThis generation began with the with the first
computers built withcomputers built with transistorstransistors – small– small
devices that transfer electronic signals acrossdevices that transfer electronic signals across
a resistor. Because transistors are mucha resistor. Because transistors are much
smaller, use less power, and create less heatsmaller, use less power, and create less heat
than vacuum tubes, the new computers werethan vacuum tubes, the new computers were
faster, smaller, and more reliable than thefaster, smaller, and more reliable than the
first generation machines.first generation machines.
Uses Integrated Circuit, commonly
known as the silicon chip, which
Users interacted through keyboards &
monitors and interfaces with an OS.
If later progressed to Large Scale
Integration (LSI), where few chips could
replace several hundred thousands of
In 1964, computer manufacturers began replacingIn 1964, computer manufacturers began replacing
transistors with integrated circuits. Antransistors with integrated circuits. An integratedintegrated
circuits (IC)circuits (IC) is a complete electronic circuit on ais a complete electronic circuit on a
small chip made of silicon (one of the most abundantsmall chip made of silicon (one of the most abundant
elements in the earth’s crust). These computers wereelements in the earth’s crust). These computers were
more reliable and compact that computers made withmore reliable and compact that computers made with
transistors, and they cost less manufacturers,transistors, and they cost less manufacturers,
Uses microprocessor, a chip which contains all
the main electronic components of a computer
If made possible to build computers to enormous
logical capacity and reliability, more cheaply and in
a very small space
Very Large Space Integration (VLSI) was
Development of GUIs, mouse & handheld devices
Microprocessors led to the development of
Many advances were made during thisMany advances were made during this
generation, the most significant being thegeneration, the most significant being the
microprocessormicroprocessor – a specialized chip– a specialized chip
developed for computer memory anddeveloped for computer memory and
logic. Use of a single chip to create alogic. Use of a single chip to create a
smaller “personal” computer (as well assmaller “personal” computer (as well as
digital watches, pocket calculators, copydigital watches, pocket calculators, copy
machines, and so on) revolutionized themachines, and so on) revolutionized the
computer industry.computer industry.
Development of artificial intelligence such as
Use of parallel processing and
superconductors to make artificial
intelligence a reality
Quantum computation & nanotechnology
will change the face of computers in years
Develop devices that responds to natural
Our current generation has been referred to asOur current generation has been referred to as
thethe “Connected Generation”“Connected Generation” because of thebecause of the
industry’s massive effort to increase theindustry’s massive effort to increase the
connectivity of computers. The rapidlyconnectivity of computers. The rapidly
expanding Internet, World Wide Web, andexpanding Internet, World Wide Web, and
intranets have created an informationintranets have created an information
superhighway that has enabled both computersuperhighway that has enabled both computer
professionals and home computer users toprofessionals and home computer users to
communicate with others across the globe.communicate with others across the globe.
Dr. John W. MauchlyDr. John W. Mauchly andand J. Presper Eckert Jr.J. Presper Eckert Jr. introduce the firstintroduce the first
commercially available electronic digital computer – thecommercially available electronic digital computer – the
UNIVAC 1 (Universal Automatic Computer)UNIVAC 1 (Universal Automatic Computer) – built with vacuum– built with vacuum
tubestubes which could perform 10,000 computations per second.
Development team led Dr. Grace Hopper,Development team led Dr. Grace Hopper,
former US Navy programmer, introduces theformer US Navy programmer, introduces the A6A6
CompilerCompiler – the first example of software that– the first example of software that
converts high level language symbols intoconverts high level language symbols into
instructions that a computer can execute.instructions that a computer can execute.
IBMIBM adds computers to its business equipmentadds computers to its business equipment
products and sells over 1000 IBM 650 systems.products and sells over 1000 IBM 650 systems.
The IBM again developed a machine
that could perform 100,000
computations per second and can
store data internally. The machine was
the IBM 704.
Introduction of first high-level programmingIntroduction of first high-level programming
language –language – FORTRANFORTRAN (FORmula TRANslator)(FORmula TRANslator)
Introduction of computers built withIntroduction of computers built with transistorstransistors – a– a
1947 Bell Laboratories invention.1947 Bell Laboratories invention.
Introduction of theIntroduction of the removable packremovable pack, providing users, providing users
with fast access to stored data.with fast access to stored data.
General Electric Corporation introducesGeneral Electric Corporation introduces ERMAERMA (Electronic(Electronic
Recording Machine Accounting)Recording Machine Accounting) – the first technology that– the first technology that
can read special characters, such as digitized information.can read special characters, such as digitized information.
Introduction of first business application programmingIntroduction of first business application programming
language –language – COBOL (Common Business Oriented Language)COBOL (Common Business Oriented Language)
– based on English-like phrases.– based on English-like phrases.
Introduction of the first computer industry standard characterIntroduction of the first computer industry standard character
set –set – ASCII (American Standard Code for InformationASCII (American Standard Code for Information
Interchange)Interchange) that enables computers to exchangethat enables computers to exchange
Introduction of computer built with anIntroduction of computer built with an integrated circuit (IC)integrated circuit (IC),,
which incorporates multiple transistors and electronic circuitswhich incorporates multiple transistors and electronic circuits
on single silicon chip.on single silicon chip.
IBM introduces itsIBM introduces its System/360System/360 line of compatible computers,line of compatible computers,
which can all use the same programs and peripherals.which can all use the same programs and peripherals.
Digital Equipment Corporation (DEC) introduces the firstDigital Equipment Corporation (DEC) introduces the first
Introduction of theIntroduction of the BASICBASIC programming language.programming language.
Introduction ofIntroduction of ARPANETARPANET and the beginning ofand the beginning of InternetInternet..
IBM announces its decision to offer unbundledIBM announces its decision to offer unbundled
software, priced and sold separately from thesoftware, priced and sold separately from the
Introduction of computers built with chips that usedIntroduction of computers built with chips that used LSILSI
(large-scale integration)(large-scale integration)
Dr. Ted Hoff of Intel Corporation develops aDr. Ted Hoff of Intel Corporation develops a
microprogrammable computer chip – the Intel 4004microprogrammable computer chip – the Intel 4004
First local area network (LAN) – Ethernet – developed atFirst local area network (LAN) – Ethernet – developed at
Xerox PARC (Palo Alto Research Center)Xerox PARC (Palo Alto Research Center)
The MITS, Inc.,The MITS, Inc., AltairAltair becomes the first commerciallybecomes the first commercially
successful microcomputer, selling for less that $400 a kit.successful microcomputer, selling for less that $400 a kit.
Apple Computer, Inc., founded byApple Computer, Inc., founded by Steve WozniakSteve Wozniak andand SteveSteve
JobsJobs, and, and Apple IApple I introduced as an easy-to-use “hobbyist”introduced as an easy-to-use “hobbyist”
Introduction of the first public information services –Introduction of the first public information services –
Compuserve and the Source.Compuserve and the Source.
IBM asks Microsoft founder,IBM asks Microsoft founder, Bill GatesBill Gates, to develop, to develop
an operating system – MS-DOS – for the soon-to-bean operating system – MS-DOS – for the soon-to-be
releasedreleased IBM personal computerIBM personal computer..
Introduction of theIntroduction of the IBM PCIBM PC, which contains an Intel, which contains an Intel
microprocessor chip and Microsoft’ MS-DOS operatingmicroprocessor chip and Microsoft’ MS-DOS operating
Apple introduces theApple introduces the Macintosh ComputerMacintosh Computer, with unique easy-, with unique easy-
to-use graphical interface.to-use graphical interface.
Microsoft introduces their Windows graphicalMicrosoft introduces their Windows graphical
user interface.user interface.
Introduction ofIntroduction of Intel 486Intel 486 – the first 1,000,000 transistor– the first 1,000,000 transistor
Microsoft releasesMicrosoft releases Windows 3.0Windows 3.0, with an enhanced graphical, with an enhanced graphical
user interface and the ability to run multiple application.user interface and the ability to run multiple application.
Release ofRelease of Word Wide WebWord Wide Web standards that describe thestandards that describe the
framework of linking documents on different computers.framework of linking documents on different computers.
Linus TorvaldsLinus Torvalds, a graduate student at the University of, a graduate student at the University of
Helsinki, develops a version ofHelsinki, develops a version of UNIXUNIX called thecalled the LinuxLinux
operating system.operating system.
Apple introduces theApple introduces the Newton MessagePadNewton MessagePad – a personal digital– a personal digital
assistant (PDA) that incorporates a pen interface and wirelessassistant (PDA) that incorporates a pen interface and wireless
Introduction of computer systems built with Intel’s PentiumIntroduction of computer systems built with Intel’s Pentium
Introduction of theIntroduction of the MosaicMosaic graphical Web browser,graphical Web browser,
which led to the organization of Netscapewhich led to the organization of Netscape
Communications CorporationCommunications Corporation
Intel begins shipping theIntel begins shipping the Pentium ProPentium Pro microprocessor.microprocessor.
Microsoft releasesMicrosoft releases Windows 95Windows 95, a major upgrade to its, a major upgrade to its
Windows operating system.Windows operating system.
More than 500 million PCs sold and more thanMore than 500 million PCs sold and more than
250 million PCs in use worldwide.250 million PCs in use worldwide.
Microsoft releasesMicrosoft releases Office 97Office 97 with major Web enhancementswith major Web enhancements
integrated into its application.integrated into its application.
The number of Internet and World Wide WebThe number of Internet and World Wide Web
users estimated at 50 million.users estimated at 50 million.
Microsoft releasesMicrosoft releases Office 98Office 98 integrated with Internet Explorerintegrated with Internet Explorer
4.0 – antitrust legislation intensifies.4.0 – antitrust legislation intensifies.
Microsoft releasesMicrosoft releases Office 2000Office 2000 featuring extensive Webfeaturing extensive Web
integration and document collaboration – soon followed byintegration and document collaboration – soon followed by
Windows 2000Windows 2000..
A private Internet –A private Internet – Internet2Internet2 – expected to be– expected to be
completed with higher speed, limited access,completed with higher speed, limited access,
and tighter security is in the works. Expectedand tighter security is in the works. Expected
to include advanced virtual reality interfacesto include advanced virtual reality interfaces
called nanomanipulators.called nanomanipulators.
In the scientific and engineering fields, it
provides inexpensive and accurate
computation for better designs of devices or
machines and more discoveries made in
In the business world, it is used in the
preparation of payrolls, in recording
accounts receivables, in keeping tracks or
In banks, insurance companies, hospitals,
and government offices, records are
Large firms and offices such as PLDT,
Meralco and MWSS prepare invoices
Provide instantaneous and accurate
data for airlines, hotels and check-out
counters in the department stores
Now becoming an everyday tool not
only in the offices but in homes as well
Why Computers Sometimes
GIGO (Garbage In Garbage Out). Computer
error may result from erroneously entered
Programs contain errors or “bugs” that do
not become evident until a specific set of
“Users” do not understand each other’s
needs or have not communicated
Improper controls can lead to sabotage the
company and invasion of privacy
Lack of standard results in problems when
an organization obtains new equipment,
hires new computer professionals, and
attempts to provide some consistent set of
procedures to be adopted by its computing
Manufacturer fails to supply needed spare
parts, trained technicians, or that particular
machine model is no longer in production
Why Computers Sometimes
Classification of Computers
General-Purpose Computers - A
computer that has the ability to store
different programs of instructions and thus
to perform a variety of operations.
Special-Purpose Computers - A
computer designed to perform one specific
According to purpose:
Digital Computers – a machine that
specialize in counting of items that are
distinct from one another, e.g. Text,
integers, Morse code
Analog Computer – machine that deals
with quantities that are continuous variable.
This means that no individual elements can
be identified from any other element, e.g.
Light, voice, and video
Hybrid Computers – machine that
combines the measuring capabilities of the
analog computer and the logical and control
capabilities of the digital computer
Classification of Computers
According to Types of data handled :
Classification of Computers
According to Capacity :
Microcomputers –capable of
handling small, single-business
applications such as sales analysis,
inventory, billing and payroll.
Minicomputers – They can do
operation like airline reservations
Medium-size Computers – They
can serve the needs of a university.
Classification of Computers
According to Capacity :
Large Computers –They can be used in
government agencies and in the
development of space technology
Supercomputers – machines that have
capabilities far beyond even the traditional
large-scale systems. They are essential for
applications ranging from nuclear weapon
development to accurate weather