History of Computer- Text Book

History of Computer

Trying to trace the history of computers, how far should we go? Computer Science is the youngest discipline among human repository of knowledge. We know, the Internet became popular among general public since 1990s; Mark I, the first computer, was built in 1944; computers have never gone earlier than 20th century?

That’s true, but, because computers are elegant devices for calculation, and if we skip the development of calculating devices, we’ll just puzzle how computers came into existence! And to understand how these devices emerged, you should know the need to calculate and count. Oh! ‘the counting devices‘? How did people start to count?

It’s strange at first to see every book on history of computers points to the ancient times – the time when mankind just developed from Stone Age. Uhh? That’s the beginning of mankind! Does the history of computers go that distant? Yes.

The First Problem – Counting

Life in jungle must be enjoying. Though, they did not have luxury of materials, their brain must be free from all the tensions of today’s world. All they cared was food and shelter. I wish Eve[1] had never eaten that apple!

The quest for easy food drove mankind into the agricultural age. People started to possess properties. When there is something you possess, you need to remember the quantity, type and so on. How many sheep do I have? How could a man express a quantity? Numbers were not invented yet!

Knots in vine and ropes, notches in sticks, scratches made on rocks must be the first counting aid for people at that time. Later on, those scratches on rocks and drawings on ground must have given a way to develop numbers.

Guess, what after the numbers came into existence? Obviously, the need to add and subtract them!

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Mechanical Devices – Counting and Calculating

In this section we will learn about the counting and calculating devices that contribute a way through for the development of modern day computers.

Abacus – The first known calculating device


Abacus[2] is a simple wooden box with beads strung which are moved towards the mid-bar[3] to perform calculations. You bring the beads near the bar and count to get result. Obtaining result is a manual process. Thus Abacus is essentially a memory aid rather than truly a calculating device. It is generally agreed that Abacus was invented in China around 2500 BC.

An Abacus is divided into two parts – heaven, the upper deck and earth, the lower deck – divided by a mid-bar. On each string there are two beads on heaven and 5 beads on earth. The value of each bead on heaven is 5 and on earth it is 1. So if you pull one heaven bead and 3 earth bead near the mid-bar, it represented the number 8.

Napier’s bones

Napiers Bones

Abacus is about ancient past. When we look upon the modern history, it is 1614 when John Napier invented Logarithm[4] – a branch of mathematics to multiply and divide extremely large or small numbers. This is considered the principal invention of Napier.

In Computer Science what interests us more about Napier’s invention, in addition to the rule of Logarithm, is Napier’s bones. It is a set of rods (10 rods in a set). Numbers are carved on each rod and can be used to perform multiplication, division with the help of logarithm. These rods were made up of bones, and must be the reason for the name.

Calculation is done by aligning the proper rods against each other and by inspection.

Slide Rule

Slide Rule

Slide Rule was invented by William Oughtred towards 1620. This device consists of logarithmic scales where one can slide upon other. The sliding rule is aligned properly against other scale and a reading is done through the indicator slide.

Slide rule could be used to perform multiplication and divisions efficiently.

Pascal’s Adding Machine – the Pascaline

17 Century was the most fertile for devising different calculating equipment. Blaise Pascal, at an age of 19 years, designed an adding machine to find the sum of numbers. The machine resulted as his effort to help his father. Pascal’s father worked in tax office and in every evening he had to calculate the sum of collection throughout the day.

It was in 1642 Pascal developed Pascaline which could be used to add, subtract, multiply and divide the numbers by dialing wheels.

Leibnitz’s Calculator – The Stepped Reckoner

German philosopher Gottfried Wilhelm von Leibnitz improved Pascal’s adding machine and made Stepped Reckoner that could even find square roots. This is the first digital mechanical calculator that can perform all four basic arithmetic operations – add, subtract, multiply and divide.

Charles Babbage and his engines

Charles Babbage is considered the father of modern computers. It is his ideas – the idea of input, mill (processing), output and storage – the modern computers followed and been successfully miraculous device! Though he could not complete his Analytical Engine (conceived in 1830s) due to insufficient funding and technological advancement of the day, it proved to be a foundation for the birth of computers.

Babbage however completed a working model of his first machine – The Difference Engine and was awarded by Royal Society. Difference engine implemented the mechanical memory to store results. It was based on the difference tables of squares of the number, and thus the name – Difference Engine.

INTERESTING FACT: Babbage conceived of a computer 100 years earlier. Howard Aikin builds the first computer Mark I based on Babbage’s idea in 1944.

Lady Augusta Ada Lovelace – The firstprogrammer

Lady Augusta Ada Lovelace was a great supporter of Charles Babbage and she convinced him to use binary systems in his engines. Because she devised a way to program Babbage’s engines, she is considered the first programmer.

Ada is the daughter of Lord Byron, a famous English poet.

US Defense developed a programming language and named it ADA to honor her contribution

Dr. Herman Hollerith & his Tabulating Machines

Herman Hollerith invented a tabulating machine for the census of 1880s. He used punched cards to code the numbers and feed them into the machine. That’s why he is considered to be the man to use punched cards practically for the first time. Though Charles Babbage used punched cards for his analytical engine, it was never built and Hollerith was successful in designing a machine that could accept input through punched cards.

Hollerith founded Tabulating Machine Company to build and sell his products and later on it was merged with some other companies to form International Business Machine (IBM) Company. IBM is the largest computer manufacturing company even today.

INTERESTING FACT: Punched cards were originally invented by Joseph Jacquard, a textile manufacturer. He used them to automate the weaving loom. These cards were later used by Charles Babbage in his design of Analytical Engine and Herman Hollerith practically used them for the first time in his Tabulating Machine.

EXTRA DOZE: Calculating devices such as Abacus, Slide Rule, and Napier’s bones etc. were very simple machines that could add, subtract and repeated operation to perform multiplication and division. Though they appear trivial today, they were great invention of that time.

By mechanical part, it means it works by moving wheels and bars. Electronic components do not have any moving parts to perform calculation and can work with the flow of electricity in its circuitry. Because it does not have moving parts, these devices are very low at failure rate.

Electro Mechanical Computers

In 1944 the first electro-mechanical computer Mark -I was built by Howard Aiken with the help of IBM. Mark I, Mark II, and Zues Computers (Z2, Z3) are the examples of Electro Mechanical Computers. Let’s look at Mark I and Z3 computer here.

Mark I

Mark-I, originally known as IBM Automatic Sequence Controlled Calculator (ASCC), is the first computer of the world. Mark-I is described as the beginning of the era of the modern computer. It was built in Harvard University by Howard H. Aiken.

Mark I was a gigantic computer. It was 51 feet long, 8 feet tall and 2 feet wide which weight 4500 Kg. It could do three additions or subtractions in a second. A multiplication took six seconds, a division took 15.3 seconds, and a logarithm or a trigonometric function took over one minute.

Device Inventor Date Specialty
Mark – I Howard Aiken 1944 First Computer

Z3 Computer

Apart from Mark I and Mark II computers, there are other contemporary computers like Z2 and Z3 (designed by Konrad Zuse) on this category.

The contribution of Zuse was ignored for long due to political reasons. He was a German Engineer and Computer Pioneer. Zuse completed his work entirely independently of other leading computer scientists and mathematicians of his day. Between 1936 and 1945, he was in near-total intellectual isolation.

Improving the basic Z2 machine, Konrad built the Z3 in 1941. It was a binary 22-bit floating point calculator featuring programmability with loops but without conditional jumps, with memory and a calculation unit based on telephone relays.

Zuse’s company (with the Z1, Z2 and Z3) was destroyed in 1945 by an Allied air attack.

Electronic Computers

In 1947 John Mauchly and J. P. Eckert developed the first general purpose electronic computer – ENIAC. This begins a new era in computing history. Apart from ENIAC, ABC, EDVAC and UNIVAC are some early electronic computers. We will be studying these computers in this section.

Calculating devices were fairly simple aid for human head. Electromechanical calculators were moderately complex. There were wheels, drums and bars that rotate and move to produce result. Because they had some mechanical parts, those devices are called electro-mechanical computers.

Electronic computers, on the other hand, work with the flow of electrons in its different components. Because electronic components are more reliable and speedy, electronic computers are very reliable compared to the earlier computers.


ABC, the first elec­tronic digital computer, was invented by John v. Atanasoff and his assistant Clifford Berry and thus the name Atanasoff Berry Com­puter (ABC).

Earlier, ENIAC was considered to be the first electronic com­puter until in 1973 a U.S. District Court invalidated the ENIAC patent. Thus, ABC is the first electronic digital computer. However, because ABC is a special purpose computer and not programmable, ENIAC still is the first general purpose electronic computer.

It is the ABC that first implements the three critical features of modern computers:

ü  Using binary digits to represent all numbers and data

ü  Performing all calculations using electronics rather than wheels, ratchets, or mechanical switches

ü  Organizing a system in which computation and memory are separated.

Device Inventor Date Specialty
ABC John v. Atanasoff & Clifford Berry 1942 First Electronic Digital Computer


ENIAC stands for Electrical Numerical Integrator And Calculator. It was developed in 1946 by John Mauchly and John Presper Eckert.

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ENIAC is the first general-purpose electronic digital computer. It used to be considered the first electronic computer till 1973 when a U.S. District Court invali­dated the ENIAC patent and concluded that the ENIAC inventors had derived the subject matter of the electronic digital computer from Atanasoff. Anyway, it is still the first general purpose electronic computer.

ENIAC used decimal numbering system for its operation and contained 17,468 vacuum tubes, along with 70,000 resistors, 10,000 capacitors, 1,500 relays, 6,000 manual switches and 5 million soldered joints. It covered 1800 square feet (167 square meters) of floor space, weighed 30 tons, and consumed 160 kilowatts of electrical power.

Note: In abbreviation the character ‘C’ in these computers stands for ‘Computer’ or ‘Calculator’. Consider both as correct.

Device Inventor Date Specialty

J.P. Eckert & John Mauchly


First General Purpose Electronic Digital Computer

EDVAC – Electronic Discrete Variable Automatic computer

Well that’s it – the name itself includes the word ‘automatic’ like ENIAC used the word ‘electronic’. ENIAC must be excited as it was not depending upon mechanical components, so, called it ELECTRONIC!

EDVAC was developed by John Mauchly and John Presper Eckert in 1949 with the help of John von Neumann.

Device Inventor Date Specialty
EDVAC J.P. Eckert & John Mauchly 1949 Stored Program Computer

EDSAC – Electronic Delay Storage Automatic Computer

EDSAC (Electronic Delay Storage Automatic Calculator) was an early British computer (one of the first computers to be created). The machine, having been inspired by John von Neumann’s seminal EDVAC report, was constructed by Professor Sir Maurice Wilkes and his team at the University of Cambridge Mathematical Laboratory in England.

EDSAC was the world’s first practical stored program electronic computer, although not the first stored program computer (that honor goes to the Small-Scale Experimental Machine).

Device Inventor Date Specialty
EDSAC Sir Maurice Wilkes 1949 The first Practical Stored Program Computer

UNIVAC – Universal Automatic Computer

After the successful development of ENIAC and EDVAC, John Mauchly& J.P. Eckert founded their own company in 1946 and began to work on the Universal Automatic computer.

UNIVAC was the first general purpose commercial computer.

Device Inventor Date Specialty
UNIVAC J.P. Eckert & John Mauchly 1951 The first general purpose commercial computer

History of Computer in Nepal

We saw the history of computers and some major innovation and pioneers in the world context. Let’s look at the history of Computers in Nepal now.

Nepal was using a calculating device called Facit to prepare census report 2018 BS (1961). Though the total population at that time was only 96 lakhs, Census Bureau could not give the exact figure of population in different districts. Due to the delay, the five year planning had to be stopped. So, for better and quicker data processing, IBM 1401 was brought on rent (Rs. 1 lakh 25 thousand per month) for the census of 2028 B.S (1971). The census processing was completed in 1 year 7 months and 15 days for 1 crore 12.5 lakhs population.

IBM 1401 however was not sent back to the owner after completing census processing but the government purchased it for further data processing in the Bureau of Statistics.

Figure 1IBM 1401 in National Computer Center, Nepal

His Majesty’s Government employed IBM 1401 in agricultural data processing, industrial data processing, inventory of Agriculture Bank, Provident fund and SLC result processing.

National Computer Center (NCC) was established in 2031 (1974) with the purpose of giving computer related service to government bodies, developing computer manpower and enhancing computer consciousness. Later on, NCC used ICL-2950/10 a second generation Mainframe computer, a DG Mini-computer, a Prime Mini-computer.

Figure 2National Computer Center, Kathmandu

With the help of ICL 2950/10, the census of 2038 BS (1981) was completed in 1 year 3 months. ICL 2950/10 was more effective and was used for data processing in some other corporations such as Telecommunication, ElectricityAuthority, JanakpurCigarette factory, Hetauda Cement Factory, Tribhuvan University, etc.

In 2039 B.S., the microcomputers, such as Apple, Vector or Siruswere imported on personal level. New companies such as Computer Consultancy(CC), Management Information Processing System(MIPS) and Data System International (DSI) were established. Now, there are manycompanies which deal with computer training, servicing, maintenance, upgrading, etc.

In 1994, Mercantile Office Systems and Royal Nepal Academy of Science and Technology contracted an Internet feed from a site in India. Since the transmission was over cable, the quality of the line was very poor and the UUCP connection was not reliable. This effort was commercialized although there were significant losses. Mercantile introduced the Internet and email in 1995 for the first time in Nepal.

Government of Nepal introduced the first IT Policy in 2000 with the vision of positioning Nepal on the global IT map within the next five years. The policy has the broad objective of enhancing employment opportunities and creating a knowledge-based society and knowledge-based industries by ensuring that a large section of society has access to information technology. The policy has adopted a 15-point strategic framework that includes human resource development, promotion of foreign and local investments, legal recognition.

Important Points to Remember

  • People used to count and calculate using knots in ropes, notches in sticks, scratches on rocks and drawing lines on ground when there were no devices to compute.
  • Abacus is the first known calculating device. It is believed that Chinese invented Abacus around 3000BC.  Abacus has two parts separated by mid-bar. The upper deck is called heaven and lower deck is earth. There are 2 beads in each string in heaven and each has value 5. There are 5 beads on earth where each beads has value 1. Calculation is done by shifting beads towards the midbar.
  • Napier’s bones was invented by a Scottish mathematician John Napier in 1617. There are 11 rods in a set of Napier’s bones and numbers are engraved in each rod. The rods are aligned properly to read the result using Napier’s bones. They could be used to multiply and divide numbers.
  • John Napier’s principal invention is Logarithm – a branch of mathematics to multiply and divide very large or very small numbers.  Napier invented Logarithm in 1614.
  • Slide Rule was invented in 1620 by English mathematician William Oughtred. Slide Rule contains two or more sliding scales which can be properly aligned and the result is obtained by inspection. It could be used to multiply and divide numbers.
  • A French mathematician Blaise Pascal invented an Adding Machine called Pascaline in 1642. It can add or subtract numbers by dialing wheels. Blaise Pascal designed this device to help his father who was a tax officer.
  • Stepped Reckoner was invented in 1671 by a German mathematician Gottfried Wilhelm von Leibnitz. Leibnitz refined Pascal’s Adding Machine and made Stepped Reckoner capable to add, subtracts, multiply, divide and even find square root.
  • Punched Card was invented by a French textile manufacturer Joseph Jacquard to automate his weaving loom. These cards later used in computers to feed data.
  • Charles Babbage designed Difference Engine in 1923 and Analytical Engine in 1933.
  • Babbage could not complete his engines mainly due to the lack of financial support and technology at that time. However, the concepts proposed for Analytical engine (input, mill and output) matches completely with the input, processing, output model of modern computers. That’s why Charles Babbage is known as Father of Computing.
  • Lady Augusta Ada Lovelace suggested Babbage to use binary numbering system for his Analytical engine and devised a method of using punched cards to calculate which made her The First Programmer. She was known as enchantress of numbers.
  • An American census statistician Dr. Herman Hollerith developed a mechanicaltabulatingmachinein1887asthe solution of tabulating problem of 1880s census. He established the Tabulating Machine Company in 1896 to manufacture and sell his inventionwhichlateronconvertedintoInternationalBusinessMachine (IBM)Company.
  • Hollerith founded Tabulating Machine Company which later merges with other three companies – InternationalTime Recording Company, Bundy Manufacturing CompanyandComputingScale Corporation to form a new company namedComputing TabulatingRecording (CTR) Corporation. In 1917 the company changes its name to International Business Machine (IBM) Co. Ltd.
  • Mark I is the first computer. Howard Aiken and American computer engineer and mathematician Grace Hoper invented it in collaboration with IBM engineers in 1937. It was an electro-mechanical computer with 18000 vacuum tubes. The machine was 51 ft. long, 8 ft. tall and 3 ft. wide.
  • Mark I is also known as Harvard-IBM Automatic Sequence Controlled Calculator(ASCC).
  • ABC (Atanasoff Berry Computer) was built in 1939-42 by John Vincent Atanasoff and Clifford Berry. It was the first electronic computer.
  • ENIAC (Electronic Numerical Integrator And Calculator) is the first general purpose electronic digital computer developed by John William Mauchly and John Presper Eckert in 1946-55. It used decimal numbering system.
  • Hungarian mathematician John von Neumann proposed Stored Program Concept in 1945. In his paper he suggested that the data as well as instructions to process those data be stored internally in the machine and binary numbering system be used for machine building.
  • EDVAC (Electronic Discrete Variable Automatic Computer) was invented by John Mauchly and J.P. Eckert in 1946-49. It was the second stored program computer.
  • Mourice Wilkes and his team in Cambridge University invented EDSAC (Electronic Delay StorageAutomatic Computer) in 1949. It is the first practical Stored Program computer.
  • UNIVAC is the first commercially available general purpose electronic digital computer. It was invented in 1951 by John Mauchly and J.P. Eckert.
  • PDP-8 is the first minicomputer introduced by DEC in 1968
  • Intel 4004 is the first microprocessor developed by Intel Corporation in 1971. This is also the first commercially available microprocessor.
  • 8 inch memory disk (floppy disk) was introduced by IBM in 1971. First sealed hard disk called Winchester was developed in 1972 by IBM.
  • MITS Altair 8800 is the first successful personal computer.
  • Microsoft Corporation founded in 1975 by Bill Gates and Paul Allen. In 1976 Job and Woznik developed the Apple personal computer. In 1984 Apple introduced Macintosh computers.
  • Apple – I personal computer was launched in 1976 by Apple Company and IBM PC was launched in 1981 by IBM Corporation.
  • In 1981 Microsoft launched “quick and dirty” DOS operating system
  • Tim Berner Lee developed World Wide Web and CERN released it in 1991.
  • Intel Corporation produced Pentium II in 1997, Pentium III in 1999 and Pentium IV in 2000.


[1] The first woman according to bible! She compelled Adam to eat the remaining half apple of knowledge

[2] Abacus is a Latin word that has its origins in the Greek words Abax or Abakon (meaning “table” or “tablet”)[Wiki Answers]

[3] A horizontal bar that separates the two parts of abacus.

[4] The method of logarithms was publicly propounded by John Napier in 1614, in a book entitled Mirifici Logarithmorum Canonis Descriptio (Description of the Wonderful Rule of Logarithms). Joost Bürgi independently invented logarithms but published six years after Napier.

2 Responses to “History of Computer- Text Book”

  • madan on August 14, 2012

    Thank you sir, I think it is the full time line of computer history, I learned new thing( about computer history and computer history of Nepal)………………thank you so much!!!!!!!!!!!