Generations of Computer 1st to 5th Difference and Characteristics

The earliest computers were large in size. These computers occupied large floor space. They consumed lot of electricity. Their cost was also higher.During last fifty years, the technological improvements have been aimed at reducing the size and electricity consumption. The aim is to reduce cost and at the same time improve the performance and speed.

The computer technology has been aimed at making smaller, cheaper and efficient computers. The development of computers has been very rapid in the last fifty years. The development has been in five distinct stages. Each of these stages is called a generation.

There are five generations

First Generation Computer (1946-1955) ENIAC

The first general purpose computer was designed to meet the requirement of World War II.

The ENIAC (Electronic Numerical Integrator and Calculator) was designed in 1945 at the University of Pennsylvania to calculate figure for thousands of gunnery tables required by the U.S. army for accuracy in artillery firing. It could perform 5000 additions or 500 multiplications per minute. It was a giant machine and needed a great amount of electricity and emitted excessive heat. ENIAC used 18,500 vacuum tubes. The main features of ENIAC can be summarized as:

• ENIAC was a general purpose computing machine in which vaccum tube technology was used. 
• ENIAC was based on decimal arithmetic rather than binary arithmetic.
• ENIAC needed to be programmed manually by setting switches and plugging or unplugging. Thus, to pass a set of instructions to computer was cumbersome and time consuming. This was considered to be the major deficiency of ENIAC.             

    A major breakthrough occurred in the logical design of computers when the concept of a stored program was proposed by Professor John Von Neumann in 1946. His idea was to store machine instructions in the memory of the computer along with data. These instructions could themselves be modified as required by other instructions. This allowed easy implementation of program loops.

 The first use of this principle was designed and commissioned at Cambridge University, U.K. under the guidance of Professor Maurice Wilkies. This computer called ED-SAC (Electronic Delay Storage Automatic Calculator) was completed in 1949 and used mercury delay lines for storage.

In 1951, Eckert and Mauchley, developed the UNI-VAC –I. This computer also used vacuum tubes. With the advent of UNI-VAC, the  prospects of commercial application were perceived. 

Characteristics of First Generation Computers

The main characteristics of first generation computers are following :-

• Vacuum tubes like diodes, triodes and resistors were used for storing data and as capacitors. Since vacuum tubes needed time to be heated, the startup time was very long and the power consumption was very high.
• An excessive amount of heat was generated and therefore these computers had to be  heavily water cooled to avoid overheating.
• They had a limited memory and programming capabilities offered by them were very limited.
• Vacuum tubes got burnt out frequently and needed to be replaced very often.
• Use of ferrite core main memory was started during this time.
• Punched cards were used as input device.
• Binary code or machine language was used for programming.
• Magnetic tapes and magnetic drums were used as secondary memory.
• Towards the end due to difficulties  encountered in use of machine language as programming language, the use of symbolic language which is now called as assembly language started. Assembler, a program which translates assembly language programs to machine language, was made.

SECOND GENERATION COMPUTERS (1955-1964)

The second generation computers with the advent of transistor replacing Vacuum Tubes. A transistor is a two state device made from silicon. It is cheaper, smaller and dissipates less heat than vacuum tube but can be utilized in a similar way as that of vacuum tubes. Unlike vacuum tubes, a glass capsule and vacuum, therefore is called a solid state device. The transistors were invented in 1947 and had launched the electronic revolution in 1950.

One of the main computer series during this time was the IBM 700 series. Each successful number of this series showed increased performance, capacity and reduced cost. In these series, two main concepts I/O channels, an independent processor for input/output and multiplexer, a useful routing device were used.

2nd generation transistor

CHARACTERISTICS OF SECOND GENERATION COMPUTERS

transistors

                The main characteristics of second generation computers are following:

Second generation computers were more advanced in terms of arithmetic and logic Unit and control  Unit than their counterparts of first generation.

• A major event during this period was the invention of magnetic cores for storage  Magnetic cores are tiny rings ( .02 inch diameter) made of fer-rite and can be magnetized in either clockwise or anti-clock wise direction. Magnetic cores were used to construct large random access memories.
• Magnetic disk storage was also developed during this period.
• The higher reliability of computers and large memory availability led to the development of high level languages. FORTRAN, COBOL , Algol were developed during this generation.

With higher speed CPU’s and the advent of magnetic tape and disk storage, operating systems were developed . Good batch operating systems, particularly the ones on IBM 7000 series computers emerged during second generation.

Commercial applications rapidly developed during this period and dominated computer use by mid 1960’s . Payroll, inventory control, marketing, production planning and general ledger systems were developed. A number of applications of operation research such as Linear Programming., Engineering applications increased rapidly.

THIRD GENERATION COMPUTERS (1965-1970)

 Transistor’s and magnetic cores were replaced by Integrated Circuits (IC’s) or Chips.In an Integrated Circuit, the components such as transistors, resistors and conductors are fabricated on semiconductor material such as silicon. Thus, a desired circuit can be fabricated in a tiny piece of silicon rather than assembling several discrete components into the same circuit. Hundreds or even thousands of transistors could be fabricated on a single wafer of silicon. In addition, these fabricated transistors can be connected with a  process of localisation to form logic circuits on the same chip they have been produced.

An integrated circuit is constructed on a thin wafer of silicon which is divided into a matrix of small areas. An identical circuit pattern is fabricated on each of these chips consists of several gates, a useful logic component, and a number of input and output in a housing to protect it. In addition, this housing provides a number of pins for connecting this chip with other devices or circuits.

Some of the examples of third generation computers are IBM system/360 Family and DEC-PDP/8 Systems.

Integrated Circuit

CHARACTERISTICS FEATURES OF THIRD GENERATION COMPUTERS 

The main characteristics features of third generation computers are following:

3rd generation integrated circuit

• IC circuits were started to find their application in the computer hardware replacing the discrete transistor component circuits. This resulted in reduction in the cost and the physical size of the computer.
• Semiconductor (Integrated circuit) memories were started to augment ferrite core memory as main memory.
• The CPU design was made simple and CPU were made more flexible using a technique called micro programming a scheme where programs control the generation of central signals.
• Certain new techniques were introduced to increase the effective speed of program execution. These techniques were pipe lining and multiprocessing.
• The operating systems of computers were incorporated with the efficient methods of sharing the facilities or resources such as processor and memory space automatically.

FOURTH GENERATION COMPUTERS (1976-1998)

With the growth in micro-electronics the IC technology evolved rapidly. One of the major milestone in this technology was the Very Large Scale Integration (VLSI)  where thousands of transistors could be integrated on a single chip. The main impact of VLSI was that, it was possible to produce a complete CPU or main memory or other similar devices on a single IC chip. This implied that mass production of CPU, memory etc. could  be done at a very low cost.

Important Breakthrough in VLSI Technology
Semiconductor Memories

Initially the IC technology was used for constructing processor but soon it was realized that the same technology could be used for construction of memory also. Therefore, the magnetic core memories were replaced by semiconductor memories.

Microprocessors

Intel in 1971 achieved the breakthrough of putting all the components on a single chip. The single chip processor is known as a microprocessor. Intel 4004 was the first microprocessor.  It was a primitive microprocessor designed for a specific application. Intel 8080 which came in 1974 was the first general purpose microprocessor. It was an 8-bit microprocessor.At present, there are 32 and 64 bit general purpose microprocessors available in the market. For example, Intel 486 is a 32 bit processor. Pentium announced by Intel can process 64 bit data at a time. VLSI technology has led to the development of Microcomputers.

VLSI technolody

CHARACTERISTICS FEATURES OF FOURTH GENERATION COMPUTERS

VLSI technolody

The main characteristics features of fourth generation computers are following:

• Medium scale integrated circuits yielded large and very large scale integrated circuits (VLSI) packing about 50,000 transistors in a chip.
• Magnetic core memories were replaced by semiconductor memories.
• Emergence of microprocessors led to the emergence of extremely powerful personal computers. Computer cost came down so rapidly that professionals had their own computer to be used in their offices and homes.
• Hard  disks provided a low cost, high capacity secondary memory.
• A major development was the decentralization of computer organization. Individual microprocessor controls for terminals and peripheral devices allowed the CPU to concentrate on processing the main program.

FIFTH GENERATION COMPUTERS (YET TO COME)

The fifth generation computers (Tomorrow’s computers) are still under research and developmental stage.

            These computers would have artificial intelligence. 

FACE RECOGNITION

They will use ULSI (Ultra Large Scale Integration) chips in place of VLSI chips.

ulsi chip technology

One ULSI chip contains millions of components on a single IC. The most important feature of fifth generation computers is that they will use an intelligence software.

THUMB IMPRESSION

 This software will enable the user to tell computer ‘what to do and what not to do’ and ‘how to do’ by using intelligence programming and knowledge based problem solving techniques.

Example: 

robots 

• ROBOTS have few features of fifth generation computers , 
• today we uses finger print sensors in our mobile phones,
• face unlock system ,  infrared are also may be the examples of fifth generation examples.

COMPARISON BETWEEN THE GENERATIONS OF COMPUTER

The comparative features of computers of various generations are shown below:

COMPARISON BTW. GENERATIONS OF COMPUTER

Introduction of Computer and Data | Computer Basics

Introduction of Computer and Data  

Computer Basics

In a relatively short time span since its invention, computer has affected many areas of our lives. For example, computers help in controlling our mobiles, act as challenging adversaries in electronic games, make possible very sophisticated medical diagnostic tools such as CAT Scanner, and even act as an ideal match-maker through computerized dating services. 

But most important, computers have a tremendous impact on the way information is processed within organizations today. Although information has been processed manually throughout history, modern management information systems would not be possible without the computers.

Computers have completely altered the structure of business. Large volumes of accounting and record keeping data can be manipulated, organized, stored, retrieved, and used for scientific purposes. Bills and statements can be processed and sent to customers in much less time and much less effort than that would be required for the same processes if carried out manually. Financial projections are made with greater ease, as the computers help managers to organize and manipulate financial data .

In manufacturing industries , computers direct production , guide machine tools, control quality, design parts, and monitor inventories.

In modern offices, word processing saves time for the employees at all levels of organization and helps insure drafting accurate letters, report and memos. Automated filing uses far less storage space than endless stacks of paper and enables workers to retrieve documents rapidly when they are needed. With more organized and consistent file systems, data management becomes more efficient.

Modern banking would be impossible without the computers. More than $500 billion a day is shifted electronically in the United States, and around $ 1000 billion globally. 

It would be difficult for the federal governments to function without computers. Economic and demographic statistics can be more easily collected, analyzed, and reported.

The Internal Revenue Service can keep better tax records. Computers aid law enforcement officials in monitoring laws and rapidly communicating information related to their duties. National defence systems are guided and managed by computer systems.

Global communication has been facilitated by the electronic transmission of data that connects individuals , regardless of geographic location, almost instantaneously.

What is Data in Computer

Data is usually a collection of facts and figures obtained on the basis of a systematic survey or study, relating to a certain activity.Series of actions taken on it to convert it into meaningful information which is helpful to user to take easy, quick and accurate decisions. 

For example : 

The examples of data in computer is describes as following point which are informative for what is data in computer-

• Students’ details (names, roll nos, marks etc.)

• Government statistics relating to trade, excise duties, taxes, census figures of population etc.

• Criminal’s details ( names, addresses, appearances, crimes etc.)

    

Evolution of Computers Difference Engine,Mark-I,Von Neumann,ENIAC,EVAC

Evolution of Computers 

Difference Engine,Mark-I,Von Neumann,ENIAC,EVAC

The computer that we use today is the result of man’s long search for a  device to help in performing computations mechanically. The search dates back to the 17^th century . A series of scientific breakthrough by many scientists have contributed to produce this electronic machine called the computer.

• If we look back at the history of computers. It can be traced back to 3000 B.C. The stone age man used small round stones  (pebbles) for counting cattle.

• Movable beads on a wire-frame constituted the first known calculating device called abacus. The abacus was used by the ancient Greeks and Romans, although significant contributions to its design were made by the Chinese. The Chinese abacus is called Suan Pan, which means counting-board. Beads are stored at one side of the frame, and calculations are performed at the other side by moving beads against that side of the frame. The significant conceptual contribution of the abacus is the use of position to represent value.

•  Mechanical Calculators- In 1642, Blaise Pascal, a French mathematician invented the first mechanical calculator. This machine is also called as Pascaline. Pascal developed a gear driven machine capable of addition, subtraction and multiplication. Manipulations were performed by rotating wheels, and a  mechanism made possible an automatic carry. The automatic carry was the significant contribution from Pascal’s machine.

            In 1671, a German mathematician Gottfried Von Leibnitz improved Pascal’s design and built a machine that multiplied, divided and determined square roots. This calculator  consisted of a cylindrical drum with several teeth along its surface. The teeth varied in length, and when the drum rotated, some of them engaged in sliding gear on the axie. This gear principle was employed in many mechanical calculators until they were replaced by electronic calculators in the 1960’s.

Jacquard's Loom

In 1801, a Frenchman named Joseph Jacquard perfected a loom that was controlled by the holes in a cardboard punched cards. The design  for woven fabric was represented by a series of holes punched in the card. In the loom’s control mechanism, mechanical fingers were activated by the presence or absence of a hole in the card. The movement of the fingers determined what threads  were to appear in the fabric. By sequencing  the cards, the loom could produce a large number of patterns and designs. When the cards for a particular pattern was automatically replaced. Jacquard’s punched were , in effect a program for the loom . There is a similarity between Jacquard’s cards and stored programs in a computer.

Charles Babbage's Difference Engine In 1812, Charles Babbage , an English  mathematician and inventor, found that certain principles from Jacquard’s loom could be used in numerical computation. Babbage called his first machine a Difference Engine and designed it to calculate logarithm tables. A series of levers were used to enter the data, and a device similar to the typewriter was used to print the output.                In 1833, Charles Babbage designed an advance form of Difference Engine called as an Analytical Engine. It was designed to add, subtract, multiply and divide through the use of a stored program . The four major components of Analytical Engine were input and output devices, an arithmetic unit to perform the calculations and a memory to store the intermediate calculations. Modern computers are based on Analytical Engine, Therefore, Charles Babbage is known as the Father of Computer.             A significant contributor to Babbage’s research was Auguta Ada Byron. Ada Byron was an accomplished mathematician who recorded and analyzed many of Babbage’s ideas. Because of her work in developing the mathematician tables, for the Analytical Engine, she is recognized as first programmer. Hollerith Census Tabulator             Herman Hollerith designed a device called the Tabulating machine, which used machine readable punched cards. Initially, Hollerith’s cards had round holes and 45 columns. His machine reduced tabulating time in 1890 census to one-eighth the time required by old methods. Hollerith founded the Tabulating Machine Company in 1896 to manufacture and sell his new inventions. In 1911, the Tabulating Machine Company merged with the International Time Recording Company , the Dayton Seale Company, and the Bundy Manufacturing Corporation to form the Computing Tabulating Recording Company (CTR). CTR was renamed as International Business Machine Corporation (IBM) in 1924.             The ATANASOFF-BERRY Computer (1939-42) – This electronic machine ws 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 vaccuum tubes for internal logic and capacitors for storage.  Aiken and Mark-I (1937-44) In 1944, Dr. Howard Aiken developed a machine called as Automatic Sequence Controlled Calculator which was later named as Mark-I             Mark-I was complex in design and huge in size. Physically, the machine measured  51 feet in length  and 8 feet in height. It is said to have contained three-quarters of a million parts and more than 5 hundred miles of wire in construction. It was extremely slow by present day standards. The addition of numbers took 0.3 part of a second and multiplication 4.5 seconds. The mark-I  was really an electro-mechanical  machine as its CPU depended on both mechanical and electronic devices for its operation. Von Neumann In1945, a significant contribution was made by John Von Neumann , a Frenchman working for IBM. He designed the basic structure of a computer to include the capacity to: Perform logical functions Perform repetitive functions Store data and instructions ENIAC (1943-46) In 1945, the fully electronic computer named ENIAC was built by Presper Eckert and John W. Mauchly. ENIAC stands for Electronic Numerical Integrator and Calculator.             It uses high speed vacuum tube switching devices. The machine was small in terms of storage capacity and as it was designed for a specific purpose (ballistics), and its use was limited. 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 directing the flow of operations. 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 and 1 to represent all characters) instead of the decimal numbers or human readable words.

Types of Computers -Super Computers, Mainframe Computers,Mini computers,Microcomputers

Types of Computers 

Super Computers, Mainframe Computers,

Mini computers,Microcomputers

Types of Computers On The Basis of Size

Computers are available in different sizes as below :

1. Super computers
2. Mainframe computers
3. Supermini and Mini Computers
4. Microcomputers

 Super Computers 

These are amongst the fastest machines in terms of processing speed, using multiprocessing techniques , where a number of processors are used to solve a problem.

 There are a number of manufacturing who dominate the market of super computers – CRAY (CRAY YMP, CRAYZ), ETA (EDC-ETA10, ETA 20) and IBM 3090 (with vector) , NEC (NEC SX-3), Fujitsu (VP Series) and HITACHI (S series).

Super computers are normally used to solve problems which require intensive numerical computations. Examples of such problems are numerical weather prediction, designing supersonic aircrafts, design of drugs and modeling complex molecules.

Super computers can carry out 10¹² floating point operations per second on 64 bit floating point numbers. Super computers have main memory of around 8 GB and a secondary memory of 1000 GB.

 Mainframe Computers

Mainframe computers are large computers and are generally 32-bit machines or on the higher side. They have very large disks to store several Giga Bytes of data and transfer data from disk to main memory at several hundred Megabytes/sec. 

The processing power  is several million transactions per second. They normally use proprietary operating systems which usually provide  extensive services such as user accounting , file security and control.

Mainframe computers are suited to big organizations, to manage high volume applications .Mainframe are also used as central host computers in distributed systems. There are a few manufacturers of mainframes such as IBM and Hitachi. Few of popular mainframe serves are MEDHA, Sperry, DEC, ICL etc.

Mini computers

Mini computer is a mini version of mainframe computer and is smaller and cheaper.

Initial mini computers were 8-bit and 12-bit machines but by 1970s almost all mini computers developed into 16 bit machines. The 16-bit mini computes have efficient storage and handling of text, in comparison to lower bit machines. A 16-bit mini computer was more powerful machine which could be used in variety of applications and could  support business applications along with the scientific applications.

With the advancement of technology , the speed, memory size and  other characteristics developed and the mini computer  was then used for various standalone or dedicated  applications. It was  then used as a multi-user system.

Gradually, the  architectural  requirement of mini computers grew and 32-bit microcomputers which were called super minis were introduced. The super minis  had more peripheral devices, large memory and could support more users working simultaneously on the computer in comparison to previous mini computers.

Microcomputers(PC-Personal Computer) 

A micro computer is a small  general purpose computer system that provides all functional elements found in larger systems. Microcomputers are based on micro-processor chips. The microcomputers originated in late 1970s.

The first microcomputer was built around 8-bit microprocessor chips. It means that the chip can retrieve instructions/data from storage, manipulate and process an 8-bit  data at a time or we can say that chip has a built-in 8-bit data transfer path. A few 8-bit microprocessor chips are Zilog Z80, Intel 8080 and MC 6809.

         An improvement of 8-bit chip technology was seen in early 1980s, when a series of 16-bit chips 8086 and 8088 were introduced by Intel corporation. 8088 is a 8/16 bit chip i.e. an 8-bit path is used to move data between chip  and primary storage, at a time, but processing is done within the chip using a 16-bit path (interval path) at a time. 8086 is a 16/16 bit chip. Intel’s 80286 is a 16/32 bit chip and can support upto 16MB of primary storage.

     Similar to Intel’s chip series, there exists  another popular chip series of Motorola. The first 16-bit microprocessor of this series is MC 68000. It is a 16/32 bit chip and can support upto 16MB of primary storage. An advancement over 16/32 bit chips are 32/32 chips. Some of the popular 32-bit chips are Intel’s 80486 and MC 68020 chips. Intel’s Pentium series chips are 32/64 bit chips.With the advancement of display and VLSI technology , now a micro-computer is available in very small size. Some of these are palmtop, laptop , notebook computers etc.

PALMTOP PC’S

With miniaturization and high density packing of transistors on a chip, computers with capabilities nearly that of PC’s which can be held in a palm have emerged. Palmtops have a tiny keyboard, small disk storage and can be connected to a wireless network. A palmtop computer has also the facilities to be used as  a mobile phone, Fax and e-mail machine.

 LAPTOP PC’S

Laptop PC’s are portable computers weighing around 2 kg. They use a keyboard, flat screen, liquid crystal display and a Pentium processor. Laptops come with all hard disk, CD-ROM and floppy disk. They should run with batteries and are thus designed to conserve energy. The most common use of Laptop computers is for travelling. They cost 3 to 4 times the cost of tabletop PC’s of the same capacity.

What is Information and Processing in Computer?

What is Information and Processing in Computer?

 Every organization keeps record of its activities in the form or raw data, facts, figures and text. All these put together are known as data. Data when represented in a useful, meaningful and arranged form is called information.

For example, an institute keeps record of its students and students details. It keeps particulars of their names, roll no. , class , addresses etc. These particulars constitute data. If we arrange the above data name-wise or roll no. wise etc., it becomes much easier and quicker to search details and get information about a student . Information is the final result obtained after the processing of data, which is meaningful to the user. 

All the organizations these days maintain a substantial amount of information on various activities. This information helps in formulating strategies and long term plans and also in keeping past records.

PROCESSING

 It is the process of transforming of data into information. In other words Processing is the series of actions taken on data to convert it into information. It include actions like :

• Calculations (Add,  Sub, Mul, Div etc.)
• Comparison (greater than, less than, equal to ,etc.)
• Sorting (arranging in some order)
• Decision making etc.

Data is the raw material with which we start. Information is processed data which is used to trigger certain actions or gain better understanding of what the data implies.

 NEED FOR INFORMATION

Everybody needs information for different purposes. There are various reasons why people seek information.Students need information relating to the prescribed syllabus for pursuing academic  studies more specifically for passing examinations.  Teachers need information for imparting education to the students. Researchers (scientists) need information continuously as they are considered the  major consumers of information.To prepare the list of selected candidates on the basis of merit. Medical and legal practitioners need information to pursue their vocations.Engineers and technologies need information for solving  technical  snag faced by  them on the shop floor. Managers (or executives) of business and industrial organizations need information to enable them to take appropriate decisions relating to issues having both short term and long term implications. They need more information for taking decisions involving managerial issues.