Computer Essentials:
Evolution of Computers
Necessity is the mother of invention. The saying holds true for computers also because computers were invented as a result of man’s search for fast and accurate calculating devices.
The earliest device that qualifies as a digital computer is the “abacus” also known as “soroban”. This device permits the users to represent numbers by the position of beads on a rack. Simple addition and subtraction can be carried out rapidly and efficiently by positioning the beads appropriately. Although, the abacus was invented around 600 B.C., it is interesting to note that it is still used in the Far East and its users can calculate at amazing speeds.
Another manual calculating device was John Napier’s bone or cardboard multiplication calculator. It was designed in the early 17th century and its upgraded versions were in use ever around 1890.
The first mechanical adding machine was invented by Blaise Pascal in 1642. Later, in the year 1671, Baron Gottfried Wilhelm von Leibniz of Germany invented the first calculator for multiplication. Keyboard machines originated in the United States around 1880 and are extensively used even today. Around this period only, Herman Hollerith came up with the concept of punched cards which are extensively used as input media in modern digital computers. Business machines and calculators made their appearance in Europe and America towards the end of the nineteenth century.
Charles Babbage, a nineteenth century Professor at Cambridge University, is considered to be the father of modern digital computers. During this period, mathematical and statistical tables were prepared by a group of clerks. Even the utmost care and precautions could not eliminate human errors. Babbage had to spend several hours checking these tables. Soon he became dissatisfied and exasperated with this type of monotonous job. The result was that he started thinking to build a machine which could compute tables guaranteed to be error-free. In this process, Babbage designed a “Difference Engine” in the year 1822 which could produce reliable tables. In 1842, Babbage came out with his new idea of Analytical Engine that was intended to be completely automatic. It was to be capable of performing the basic arithmetic functions for any mathematical problem and it was to do so at an average speed of 60 additions per minute. 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 which have been shown to be fundamental to the design of any digital computer. We will now discuss about some of the well-known early computers.
THE MARK I COMPUTER (1937-44)
Also known as Automatic Sequence Controlled calculator, this was the first fully automatic calculating machine designed by Howard A. Aiken of Harvard University in collaboration with IBM (International Business Machines) corporation. Its design was based on the techniques already developed for punched card machinery.
Although this machine proved to be extremely reliable, it was very complex in design and huge in size. It used over 3000 electrically actuated switches to control its operations and was approximately 50 feet long and 8 feet high. It was capable of performing five basic arithmetic and table reference. A number as big as 23 decimal digits could be used in this machine. It took approximately 0.3 second to add two numbers and 4.5 seconds for multiplication of two numbers. Hence, the machine was very slow as compared to todays computers.
It was basically an electro-mechanical device since both mechanical and electronic components were used in its design. Although its operations were not controlled electronically, Aiken’s machine is often classified as computer because its instructions, which were entered by means of punched paper tape, could be altered.
THE ATANASOFF – BERRY COMPUTER (1939-42)
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 and his assistant, Clifford Berry. It used 45 vacuum tubes for internal logic and capacitors for storage.
THE ENIAC (1943-46)
The Electronic Numerical Integrator And Calculator (ENIAC) was the first all-electronic computer. It was constructed at the Moore School of Engineering of the University of Pennsylvania, U.S.A by a design team led by Professors J. Presper Eckert and John Mauchly.
ENIAC was developed as a result of military need. It took up the wall space in a 20*40 square feet room and used 18,000 vacuum tubes. The addition of two numbers was achieved in 200 microseconds, and multiplication in 2000 microseconds.
Although, much faster in speed as compared to Mark I computer, ENIAC had two major shortcomings: it could store and manipulate only a very limited amount of information, and its programs were wired on boards. These limitations made it difficult to detect errors and to change the programs. Hence its use was limited. However, whatever be the shortcomings of ENIAC, it represented an impressive feat of electronic engineering and was used for many years to solve ballistic problems.
THE EDVAC (1946-52)
The operation of ENIAC was seriously handicapped by the wiring board. This problem was later overcome by the new concept of “stored program” developed by Dr. John Von Neumann. The basic idea behind the stored program concept is that a sequence of instructions as well as data can be stored in the memory of the computer for the purpose of automatically directly the flow of operations. The stored program feature considerably influenced the development of modern digital computers. The Electronic Discrete Variable Automatic Computer (EDVAC) was designed on stored program concept. Von Neumann has also got a share of the credit for introducing the idea of storing both instructions and data in the binary form (a system that uses only two digits – 0 & 1 to represent all characters) instead of the decimal numbers or human readable words.
THE EDSAC (1947-49)
Almost simultaneously with EDVAC of U.S.A., the Britishers developed the Electronic Delay Storage Automatic Calculator (EDSAC). The machine executed its first program in May 1949. In this machine, addition operations was accomplished in 1500 microseconds, and multiplication operation in 4000 microseconds. The machine was developed by a group of scientists headed by Professor Maurice Wilkes at the Cambridge University Mathematical Laboratory.
MANCHESTER MARK I (1948)
This computer was a small experimental machine based on the stored program concept. It was designed at Manchester University by a group of scientists headed by Professor M.H.A. Newmann. Its storage capacity was only 32 words, each of 31 binary digits. This was too limited to store data and instructions. Hence, the Manchester Mark I was hardly of any practical use.
THE UNIVAC I (1951)
The Universal Automatic Computer (UNIVAC) was the first digital computer which was not “one kind of a kind”. Many UNIVAC machines were produced, the first of which was installed in the Census Bureau in 1951 and was used continuously for 10 years. The first business use of a computer, a UNIVAC I, was by General Electric Corporation in 1954.
In 1952, the International Business Machines (IBM) Corporation introduction the 701 commercial computer. In rapid succession, improved models of the UNIVAC I and other 700-series machines were introduced. In 1953, IBM produced the IBM-650 and sold over 1000 of these computers.
The commercially available digital computers, that could be used for business and scientific applications, had arrived.
Download our app for Exam Preparation Click Here
For Preparation of other Exams like U.P D.El.Ed/B.T.C, UP TET, REET, HTET, BTET, OTET, UTET, CTET, KVS, DSSSB, Super TET, UGC Net, and all state teaching examination Click Here
#Tet Aspirant
#Computer Notes for UPSI, UP Police, U.P D.El.Ed/B.T.C, UP TET, REET, HTET, BTET, OTET, UTET, CTET, KVS, DSSSB, Super TET, UGC Net, and all state teaching examination
#Computer Essentials: Evolution of Computers
#Evolution of Computers
#Computer Fundamentals
#THE MARK I COMPUTER
#THE UNIVAC I
#MANCHESTER MARK I
#THE EDSAC
#THE EDVAC
#THE ENIAC
#THE ATANASOFF – BERRY COMPUTER