Necessity is the mother of invention. This saying is true to computers because computers were invented as a result of man’s search for fast and accurate calculation purposes. In earlier days, people used their fingers, stones, and pebbles to do calculations. The earliest device which is used for the calculation is an Abacus. There are lots of efforts made by mathematicians and physicists to convert the calculating device (Abacus) to modern computers. The developments of calculating devices to the modern computers are:
Fig. Evolution of computers


Abacus is one of the first mechanical calculating devices invented by the Chinese about 3000 years ago. An Abacus consists of a rectangular frame carrying a number of rods or wires. A transverse bar (center bar) divides each of these rods into two unequal proportions. On the upper smaller portion of each rod, there are two beads and on the lower portion, there are five beads. Each bead on the upper portion has the value of five while the lower portion has the value of one. Calculations are performed by placing the abacus flat on a surface and moving the beads towards the mid bar.

Napier’s Bone

A scottish mathematician, John Napier invented Napier’s bone in 1617 AD. he also played a key role in the development of Logarithms. This device is made up of a number of rods where multiplication tables were engraved. This device was capable of performing multiplications and division.

Slide Rule

Willian Oughtred, an English mathematician invented the slide rule in 1620AD. This device is considered the first analog computing device which works on the principle of logarithms. It has two movable graduated rulers kept side by side. Each ruler is marked off in such a way that the actual distance from the beginning of the ruler is proportional to the logarithm of the number printed in the ruler.


The first mechanical calculator called Pascaline was invented by Blaise Pascal, a French mathematician, in 1642 AD. This machine was capable of performing additions and subtractions while multiplications and division were implemented by repeated additions and subtractions. A computer programming language “Pascal” was letter named to honor his contribution.

Stepped Reckoner

In 1694 AD, a German mathematician and philosopher, Gottfried Welham Von Leibniz improved the Pascaline by creating a machine called Stepped Reckoner that could add, subtract, multiply and evaluate square roots by series of stepped additions. Leibniz was the first to advocate the use of a binary number system.

Jacquard’s Loom

In 1804, a French silk weaver called Joseph Marie Jacquard designed an automated loom that used punched cards as a pattern to weave intricate patterns. The function of the loom depended upon the presence or absence of holes on the card. jacquard’s loom was considered the first practical method of processing information.

Babbage’s engine (Difference & Analytical Engines)

Charles Babbage, a nineteenth-century Professor at Cambridge University, is considered to be the father of modern digital computers. During his period, mathematical and statistical tables were prepared by a group of clerks. He had to spend several hours checking these tables. So, he started thinking of building a machine that could compute tables to be error-free. In this process, Babbage designed the “Difference Engine” in the year 1822 AD which could produce reliable tables. In 1833 AB, Babbage came out with his new idea “Analytical Engine” which was intended to be completely automatic. Unfortunately, he was unable to produce a working model of this machine mainly because the precision engineering required to manufacture the machine was not available during that period. However, his efforts established a number of principles that are fundamental to the design of any digital computer. This is the reason why Charles Babbage is considered the “father of the modern computers”.

Lady Augusta Ada Lovelace

Lady Ada Lovelace was eh lady who prepared extensive notes concerning Babbage’s idea and the analytical engine. She was an assistant to Charles Babbage. She suggested Charles Babbage use a binary number system for programs and data to be fed into an analytical engine. She is considered the first computer programmer. A programming language named “Ada” is named after her.

Tabulating Machine

Herman Hollerith was an American census statistician who worked for the US Census Bureau. The Census Bureau held a contest to see if anyone could invent a faster the machine to compute the US census. Hollerith devised the first “Tabulating Machine” in 1887.
This machine was used to tabulate the 1890 US census in a record time. Hollerith established the Tabulating Machine Company in 1896 to manufacture his inventions. Later, his company was merged with other companies to form International Business Machine (IBM) in 1924 AD.

Mark-I (1937-1944)

Mark-I is also known as Automatic Sequence Controlled Calculator (ASCC). This was the first fully automatic calculating machine designed by Howard Aiken of Harvard University in collaboration with IBM (International Business Machine) corporation. It was very complex in design and huge in size. It was about 50feet long and 8feet high, 3fee wide having 18000 vacuum tubes. This machine was very slow as compared to today’s computers. It was basically an electro-mechanical device since both mechanical and electronic components were used in its design.

Atanasoff Berry Computer (1937-1942)

This electronic machine was developed by Dr. John Atanasoff to solve certain mathematical equations. It was called the Atanasoff-berry computer, or ABC after its inventor’s name John Atanasoff and his assistant, Clifford Berry. It used 45 vacuum tubes for internal logic and capacitors for storage. It was the first complete machine that had used binary arithmetic.

Electronic Numerical Integrator and Calculator (1943-1946)

The Electronic Numerical Integrator and Calculator (ENIAC) was the first general-purpose electronic computer. It was constructed at the Moore School of Engineering of the University of Pennsylvania, USA by a design team lead by Professor J. Presper Eckert and John Mauchly. ENIAC was developed as a result of military need. It used about 18000 vacuum tubes, 10000capacitors, and 70000registers. The problem of ENIAC was that it could store and manipulate only a limited amount of information. ENIAC is commonly accepted as the first successful high-speed electronic digital computer (EDC) and was used from 1946 to 1955.

Electronic Discrete Variable Automatic Computer (1946-1952)

The problem of ENIAC was overcome by the new concept called the “stored program concept” developed by Dr. John Von Neumann. The basic idea behind the stored program concept is that a sequence of instructions and data can be stored in the memory of the computer. The EDVAC was designed on the stored program concept. it contained approximately 4000 vacuum tubes and 10000 crystal diodes.

Electronic Delay Storage Automatic Computer (1947-1949)

Almost simultaneously with EDVAC of the USA, the Britishers developed the Electronic Delay Storage Automatic Calculator (EDSAC). The machine was developed by a group of scientists headed by Professor Maurice Wilkes at the Cambridge University, England, in May 1949AD. It was made up of 3000 vacuum tubes and consumed 30 kilowatts of electric power.

Universal Automatic Computer (1951)

The Universal Automatic Computer (UNIVAC-I) was the first digital computer designed for commercial use. It was produced by universal Accounting Company set up by John Mauchly and J.P. Eckert in 1951. It was based on EDVAC design. It became operational at the Census Bureau in early 1951 for use in census taking.



History of Computer in Nepal

The history of computers in Nepal, Takes back to 2028 BS, when a second-generation IBM 1401 computer, was initially hired on rent by his Majesty’s Government, paying Rs. One Lakh twenty-five thousand per month to use in the census of that year. IBM 1401 took 1year, 7months, and 15days to process 1crore and 12.5 lakhs population. Later, this computer was purchased by the government for further data processing in the Bureau of Statistics.
For the proper use of this computer, Electronic Data Processing Centre was established in 2031BS. After 6years, it was named as National Computer Centre (NCC).
Another British model computer called ICL 2950/10 was purchased for the census of 2038 BS. It was funded by UNDP and UNFPA at two million American Dollars. the census of 2038 was completed within a year and a quarter with the help of this computer.
Microcomputers like Apple, Vector, and Sirus entered in the year 2039 BS. Initially, there were only three companies like Management Information Processing System (MIPS), Computer Consultancy, and Data System International. But now, there are man companies in Nepal, which impart training and provide the service of programming, computer supply, and maintenance.
The Government has formed a High Commission for Information Technology (HCIT) under the chairmanship of the Prime Minister. IT Policy was also formulated in 2057 BS. IT Park with all infrastructures of IT companies is in Banepa of Kavrepalanchowk district.

Generation of Computer


The evolution of modern digital computing is often divided into ‘generations’ which started from the early forties to date. The term ‘generation of computer’ refers to the major developments in electronic data processing over a period of time. Each generation is characterized by dramatic improvements over the previous generation in the technology used to build computers, the internal architecture of computer systems, the programming languages used, and so on. The development of the computer took place in five distinct phases known as computer generations. Evaluation of modern computers is classified into five main components used and programming languages used by them.

a. First Generation Computer (1946-1959)

The first generation of computers was developed from 1946 to 1959. We have already discussed some of the early computers – ENIAC, EDVAC, EDSAC, and others. These machines were made possible by the invention of the vacuum tube. A vacuum tube was a fragile glass device that could control and amplify electronic signals. First-generation computers also used vacuum tubes as their basic electronic component.
Fig. Vacuum Tube


The main features of First Generation Computers are:

  • They emitted a large amount of heat because of their big size.
  • These computers were the fastest calculating device of their time. They could perform calculations in milliseconds.
  • They were unreliable.
  • They required air conditioning.
  • They were prone to frequent hardware failures.
  • Their commercial use was limited.
  • Machine language was used to program these computers.
Some of the examples of first-generation computers are ENIAC, EDVAC, EDSAC, UNIVAC, and so on.

b. Second Generation computer (1959-1965)

Second-generation computers were developed from 1959 to 1965. The transistor, a smaller and more reliable successor to the vacuum tube, was invented by three scientists J. Bardeen, H.W. Brattain, and W. Shockley in 1947. A transistor is a small device made up of semiconductor materials like germanium and silicon. Second-generation computers came with transistors being the brain of the computer.
Fig. Transistors

The main features of second-generation computers are:

  • They were smaller in size as compared to first-generation computers as they used transistors as their basic component.
  • They were more reliable.
  • They emitted less heat.
  • They were less prone to hardware failure.
  • They had wider commercial use.
  • They were able to reduce computational times from milliseconds to microseconds.
  • They required air-conditioning.
  • They require frequent maintenance.
  • They required manual assembly of individual components into a functioning unit.
  • Their commercial production was difficult and costly.
  • Assembly language was used to program these computers.
Examples of second-generation computers are IBM 7000, NCR 304, IBM 1401, IBM 1620, ATLAS, MARK-III, and so on.

c. Third Generation Computer (1965-1971)

The third generation computers were developed during the period 1965 to 1971. Advancement in electronic technology continued and the invention of microelectronics technology made it possible to integrate a large number of circuit elements into a very small surface of silicon known as chips. The new technology was called integrated circuits (ICs). IC was developed by Robert Noyce and Jack Kilby at Texas Instrument in 1958-1959. The third generation computers were based on IC technology and the computers that were designed with the use of integrated circuits were called third-generation computers.
Fig. IC chips


The main Features of Third generation computers are:

  • They used ICs as their main component.
  • They were smaller in size as compared to second-generation computers.
  • They were even more reliable than second-generation computers.
  • They generated low heat than second-generation computers.
  • These computers were able to reduce the computational time from microseconds to nanoseconds.
  • They didn’t require manual assembly of individual components into a functional unit.
  • They required highly sophisticated technology for manufacturing IC chips.
  • High-level languages were used to program these computers
Some of the examples of third-generation computers are PDP-8, PDP-11, ICL 2900 series, IBM 360, IBM 370 series, and so on.

d. Fourth Generation Computer (1971-1990)

The fourth-generation computers were developed during 1971-1990. They were the extension of third-generation computers. They used Very Large Scale Integration (VLSI) chips as their main component. It is the VLSI technology that has led to the development of very small but extremely powerful computers. They were very inexpensive to make and suddenly it became possible for anyone and everyone to own a computer.
Fig. Micro Processor Chip (VLSI)

The main features of fourth generation computers are:

  • They use VLSI chips as their main component.
  • They are the smallest computers.
  • They generate negligible heat.
  • They are much faster in computation.
  • They are easily portable as they are small in size.
  • They are the cheapest of all the computers.
  • They are the cheapest of all computers.
  • They have larger memory and speed.
  • They use high-level languages to program them.
Some of the examples of fourth-generation computers are IBM PC, Apple/Macintosh, IBM 4341, DEV 10, STAR 1000, PUP 11, APPLE II, and so on.

e. Fifth Generation Computer (1991 onwards)

Scientists are now at work on the fifth generation computers -a promise, but not yet a reality. They aim to bring us machines with genuine I.Q., the ability to reason logically and with real knowledge of the world. In nature, it will not do just data processing but knowledge processing. In application, it will behave like an expert. In programming, it will interact with humans in ordinary language. They will have artificial intelligence.

The features of fifth-generation computers are:

  • They will use Ultra Large Scale Integration (ULSI) chips as their main component.
  • They will have artificial intelligence.
  • They will use superconductor technology.
  • They will do parallel processing.
  • They will be able to recognize images and graphs.
  • They will do multiprocessing for faster operations.


Similar Posts


Leave a Reply

Your email address will not be published. Required fields are marked *