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HISTORY OF COMPUTER

              HISTORY OF COMPUTER SHOW 

                              This chapter is a brief summary of the history of Computers. It is supplemented by the two PBS documentaries video tapes "Inventing the Future" And "The Paperback Computer". The chapter highlights some of the advances to look for in the documentaries.
         In particular, when viewing the movies you should look for two things:

• The progression in hardware representation of a bit of data:
  1. Vacuum Tubes (1950s) - one bit on the size of a thumb;
  2. Transistors (1950s and 1960s) - one bit on the size of a fingernail;
  3. Integrated Circuits (1960s and 70s) - thousands of bits on the size of a hand
  4. Silicon computer chips (1970s and on) - millions of bits on the size of a finger nail.
  
  
• The progression of the ease of use of computers:
  1. Almost impossible to use except by very patient geniuses (1950s);
  2. Programmable by highly trained people only (1960s and 1970s);
  3. Useable by just about anyone (1980s and on).

•            First Computers

                                                             The first substantial computer was the giant ENIAC machine by John W. Mauchly and J. Presper Eckert at the University of Pennsylvania. ENIAC (Electrical Numerical       Integrator and Calculator) used a word of 10 decimal digits instead of binary ones like previous automated calculators/computers.  ENIAC was also the first machine to use more than 2,000 vacuum tubes, usingnearly 18,000 vacuum tubes. Storage of all those  vacuum tubes and the machinery required to keep the cooltook up  over 167 square meters (1800 square feet) of floor space. Nonetheless, it had punched-card inputand output and arithmetically had 1 multiplier, 1 divider-square rooter, and 20 adders employing decimal "ring counters," which served as addersand also as quick-access (0.0002 seconds) read-write register storage. 

Eniac Computer

                                                               The executable instructions composing a program were embodied in the separate units of ENIAC, which were plugged together to form a route through the machine for the flow of computations. These connections had to be redone for each different problem, together with presetting function tables and switches. This "wire-your-own" instruction technique was inconvenient, and only with some license could ENIAC be considered programmable; it was, however, efficient in handling the particular programs for which it had been designed. ENIAC is generally acknowledged to be the first successful high-speed electronic digital computer (EDC) and was productively used from 1946 to 1955. A controversy developed in 1971, however, over the patentability of ENIAC's basic digital concepts, the claim being made that another U.S. physicist, John V. Atanasoff, had already used the same ideas in a simpler vacuum-tube device he built in the 1930s while at Iowa State College. In 1973, the court found in favor of the company using Atanasoff claim and Atanasoff received the acclaim he rightly deserved.

• Progression of Hardware

In the 1950's two devices would be invented that would improve the computer field and set in motion the beginning of the computer revolution. The first of these two devices was the transistor. Invented in 1947 by William Shockley, John Bardeen, and Walter Brattain of Bell Labs, the transistor was fated to oust the days of vacuum tubes in computers, radios, and other electronics.

Vaccum Tubes

The vacuum tube, used up to this time in almost all the computers and calculating machines, had been invented by American physicist Lee De Forest in 1906. The vacuum tube, which is about the size of a human thumb,worked  by using large amounts of electricity to heat a filament inside the tube until it was cherry red. One result of heating this filament up was the release of electrons into the tube, which could be controlled by other elements within the tube. De Forest's original device was a triode, which could control the flow of electrons to a positively charged plate inside the tube. A zero could then be represented by the absence of an electron current to the plate; the presence of a small but


 Transistors
Vacuum tubes were highly inefficient, required a great deal of space, and needed to be replaced often. Computers of the 1940s and 50s had 18,000 tubes in them and housing all these tubes and cooling the rooms from the heat produced by 18,000 tubes was not cheap. The transistor promised to solve all of these problems and it did so. Transistors, however, had their problems too. The main problem was that transistors, like other electronic components, needed to be soldered together. As a result, the more complex the circuits became, the more complicated and numerous the connections between the individual transistors and the likelihood of faulty wiring increased.

In 1958, this problem too was solved by Jack St. Clair Kilby of Texas Instruments. He manufactured the first integrated circuit or chip. A chip is really a collection of tiny transistors which are connected together when the transistor is manufactured. Thus, the need for soldering together large numbers of transistors was practically nullified; now only connections were needed to other electronic components. In addition to saving space, the speed of the machine was now increased since there was a diminished distance that the electrons had to follow.

Transistors

Vacuum tubes were highly inefficient, required a great deal of space, and needed to be replaced often.Computers of the 1940s and 50s had 18,000 tubes in them and housing all these tubes and cooling the rooms from the heat produced by 18,000 tubes was not cheap. The transistor promised to solve all of these problems and it did so. Transistors, however, had their problems too. The main problem was that transistors, like other electronic components, needed to be soldered together. As a result, the more complex the circuits became, the more complicated and numerous the connections between the individual transistors and the likelihood of faulty wiring increased.

In 1958, this problem too was solved by Jack St. Clair Kilby of Texas Instruments. He manufactured the first integrated circuit or chip. A chip is really a collection of tiny transistors which are connected together when the transistor is manufactured. Thus, the need for soldering together large numbers of transistors was practically nullified; now only connections were needed to other electronic components. In addition to saving space, the speed of the machine was now increased since there was a diminished distance that the electrons had to follow.

Circuit Board	Silicon Chip

• Mainframes to PCs

The 1960s saw large mainframe computers become much more common in large industries and with the US military and space program. IBM became the unquestioned market  leader in selling these large, expensive, error-prone, and very hard to use machines.
A veritable explosion of personal computers occurred in the early 1970s, starting with Steve job and Steve Wozniak exhibiting the first Apple II at the First West Coast Computer Faire in San Francisco. The Apple II boasted built-in BASIC programming language, color graphics, and a 4100 character memory for only $1298. Programs and data could be stored on an everyday audio-cassette recorder. Before the end of the fair, Wozniak and Jobs had secured 300 orders for the Apple II and from there Apple just took off.
Also introduced in 1977 was the TRS-80. This was a home computer manufactured by Tandy Radio Shack. In its second incarnation, the TRS-80 Model II, came complete with a 64,000 character memory and a disk drive to store programs and data on. At this time, only Apple and TRS had machines with disk drives. With the introduction of the disk drive, personal computer applications took off as a floppy disk was a most convenient publishing medium for distribution of software.
IBM, which up to this time had been producing mainframes and minicomputers for medium to large-sized businesses, decided that it had to get into the act and started working  on the Acorn, which would later be called the IBM PC. The PC was the first computer designed for the home market which would feature modular design so that pieces could easily be added to the architecture. Most of the components, surprisingly, came from outside of IBM, since building it with IBM parts would have cost too much for the home computer market. When it was introduced, the PC came with a 16,000 character memory, keyboard from an IBM electric typewriter, and a connection for tape cassette player for $1265.
By 1984, Apple and IBM had come out with new models. Apple released the first generation Macintosh, which was the first computer to come with a graphical user interface(GUI) and a mouse. The GUI made the machine much more attractive to home computer users because it was easy to use. Sales of the Macintosh soared like nothing ever seen before. IBM was hot on Apple's tail and released the 286-AT, which with applications like Lotus 1-2-3, a spreadsheet, and Microsoft Word, quickly became the favourite of business concerns.
That brings us up to about ten years ago. Now people have their own personal graphics workstations and powerful home computers. The average computer a person might have in their home is more powerful by several orders of magnitude than a machine like ENIAC. The computer revolution has been the fastest growing technology in man's history.




Present by Ashok Chudasama




















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Generations Of Computer

 GENERATION OF COMPUTERS

                                         The first electronic computer was designed and built at the University of Pennsylvania based on vacuum tube technology. Vacuum tubes were used  to perform logic operations and to store data. Generations of computers has been divided into five according to the development of technologies used to fabricate the processors, memories and I/O units.          

                                              

•                                                                                                           First Generation (1941-1956)

 

 World War gave rise to numerous developments and started off the computer age.Electronic Numerical Integrator and Computer (ENIAC) was produced by a partnershp between University of Pennsylvannia and the US government. It consisted of 18,000vacuum tubes and 7000 resistors. It was developed by John Presper Eckert and John W.Mauchly and was a general purpose computer. "Von Neumann designed the ElectronicDiscrete Variable Automatic Computer (EDVAC) in 1945 with a memory to hold both astored program as well as data." Von Neumann's computer allowed for all the computer functions to be controlled by a single source.Then in 1951 came the Universal Automatic Computer(UNIVAC I), designed byRemington rand and collectively owned by US census bureau and General Electric.UNIVAC amazingly predicted the winner of 1952, presidential elections,

Dwight D.Eisenhower.In first generation computers, the operating instructions or programs were specifically built for the task for which computer was manufactured. The Machine language was theonly way to tell these machines to perform the operations. There was great difficulty to program these computers ,and more when there were some malfunctions. FirstGeneration computers used Vacuum tubes and magnetic drums(for data storage).

• Second Generation Computers (1956-1963)

 The invention of Transistors marked the start of the second generation. These transistorstook place of the vacuum tubes used in the first generation computers. First large scalemachines were made using these technologies to meet the requirements of atomic energylaboratories. One of the other benefits to the programming group was that the secondgeneration replaced Machine language with the assembly language. Even thoughcomplex in itself Assemly language was much easier than the binary code.Second generation computers also started showing the characteristics of modern daycomputers with utilities such as printers, disk storage and operating systems. Manyfinancial information was processed using these computers.In Second Generation computers, the instructions(program) could be stored inside thecomputer's memory. High-level languages such as COBOL (Common Business-OrientedLanguage) and FORTRAN (Formula Translator) were used, and they are still used for some applications nowdays.

•   Third Generation Computers (1964-1971)

The invention of Transistors marked the start of the second generation. These transistorstook place of the vacuum tubes used in the first generation computers. First large scalemachines were made using these technologies to meet the requirements of atomic energylaboratories. One of the other benefits to the programming group was that the secondgeneration replaced Machine language with the assembly language. Even thoughcomplex in itself Assemly language was much easier than the binary code.Second generation computers also started showing the characteristics of modern daycomputers with utilities such as printers, disk storage and operating systems. Manyfinancial information was processed using these computers.In Second Generation computers, the instructions(program) could be stored inside thecomputer's memory. High-level languages such as COBOL (Common Business-OrientedLanguage) and FORTRAN (Formula Translator) were used, and they are still used for some applications nowdays.   Circuit(IC) was invented in 1958 by Jack Kilby. It combined electronic components ontoa small silicon disc, made from quartz. More advancement made possible the fitings of even more components on a small chip or a semi conductor. Also in third generationcomputers, the operating systems allowed the machines to run many differentapplications. These applications were monitored and coordinated by the computer'smemory

•   Fourth Generation (1971-Present)

Fourth Generation computers are the modern day computers. The Size started to go downwith the improvement in the integerated circuits. Very Large Scale(VLSI) and UltraLarge scale(ULSI) ensured that millions of components could be fit into a small chip. Itreduced the size and price of the computers at the same time increasing power, efficiencyand reliability. "The Intel 4004 chip, developed in 1971, took the integrated circuit onestep further by locating all the components of a computer (central processing unit,memory, and input and output controls) on a minuscule chip."Due to the reduction of cost and the availability of the computers power at a small placeallowed everyday user to benefit. First came the minicomputers, which offered usersdifferent applications, most famous of these the word processors and spreadsheets, whichcould be used by non-technical users. Video game systems like Atari 2600 generated theinterest of general populace in the computers.In 1981, IBM introduced personal computers for home and office use. "The number of  personal computers in use more than doubled from 2 million in 1981 to 5.5 million in1982. Ten years later, 65 million PCs were being used." Computer size kept gettingreduced during the years. It went down from Desktop to laptops to Palmtops. Machintoshintroduecd Graphic User Interface in which the users didnt' have to type instructions butcould use Mouse for the purpose.The continued improvement allowed the networking of computers for the sharing of data.Local Area Networks(LAN) and Wide Area Network(WAN), were potential benefits, inthat they could be implemented in corporations and everybody could share data over it.Soon the internet aand World Wide Web appeared on the computer scene and formentedthe Hi-Tech revolution of 90's

Fifth Generation (Present and Beyond)

 Fifth generations computers are only in the minds of advance research scientiets and being tested out in the laboratories. These computers will be under ArtificalIntelligence(AI), They will be able to take commands in a audio visual way and carry outinstructions. Many of the operations which requires low human intelligence will be perfomed by these computers.Parallel Processing is coming and showing the possibiliy that the power of many CPU'scan be used side by side, and computers will be more powerful than thoes under centraL.

 processing. Advances in Super Conductor technology will greatly improve the speed of information traffic. Future looks bright for the computers.




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