Evolution of Computers

EVOUTION OF COMPUTERS
The evolution of electronic computers over a period of time can be traced effectively dividing this period into various generations. Each generation is characterized by a major technological development that fundamentally changed the way computers operated. These helped to develop smaller, cheaper, powerful, efficient and reliable devices. Today, life has become indispensable without a computer. You find computerization in almost every sphere and industry. Computer evolution has been a fascinating process as we find out here.
The generation of computers may be broadly classified into 5 stages :
1. First Generation ( 1940 – 1956 )
2. Second Generation ( 1956 – 1963 )
3. Third Generation ( 1964 – 1971 )
4. Fourth generation ( 1971 – Present )
5. Fifth Generation ( present and Beyond )

FIRST GENERATION ( 1940 – 1956 )
World War gave rise to numerous developments and started off the computer age. Electronic Numerical Integrator and Computer (ENIAC) was produced by a partnership between University of Pennsylvannia and the US government. It consisted of 18,000 vacuum 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 Electronic Discrete Variable Automatic Computer (EDVAC) in 1945 with a memory to hold both a stored 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 by Remington 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 the only way to tell these machines to perform the operations. There was great difficulty to program these computers ,and more when there were some malfunctions.
The first generation of computers used vacuum tubes for circuitry and magnetic drums for memory. They were large in size, occupied a lot of space and produced enormous heat.
They were very expensive to operate and consumed large amount of electricity. Input was based on punched cards and paper tape and output was displayed on print outs. First generati0n computers could solve only one problem at a time.

SECOND GENERATION(1956– 1963)
The second generation of computers witnessed the vacuum tubes being replaced by the “ TRANSISTORS “. The transistor was far superb, faster, cheaper, energy-efficient and more reliable than their First- generation counter parts. The transistors also generated considerable heat that sometimes caused the computer to malfunction. But it was a vast improvement over the vacuum tube. Second-generation computers used punched cards for input and print outs for output.
Second generation computers moved from the use of machine language to assembly language, which allowed programmers to specify instructions in words. Even though complex in itself Assembly language was much easier than the binary code. High-level programming languages were also developed at this time, such as early version of COBOL (Common Business-Oriented Language) and FORTRAN (Formula Translator). The computers stored their instruction in their memory, which moved from a magnetic drum to magnetic core technology. Throughout the early 1960's, there were a number of commercially successful second generation computers used in businesses, universities, and government from companies such as Burroughs, Control Data, Honeywell, IBM, Sperry-Rand, and others. These second generation computers were also of solid state design, and contained transistors in place of vacuum tubes. They also contained all the components we associate with the modern day computer: printers, tape storage, disk storage, memory, and stored programs. One important example was the IBM 1401, which was universally accepted throughout industry, and is considered by many to be the Model T of the computer industry. By 1965, most large business routinely processed financial information using second generation computers (Gersting 218).

THIRD GENERATION ( 1964 – 1971 )
The development of the Integrated Circuit in 1958 by Jack Kilbey left its mark in the third generation of computers. Transistors were made smaller in size and placed on silicon chips, which dramatically increased the speed and efficiency of computers. As a result, computers became ever smaller as more components were squeezed onto the chip. Another third-generation development included the use of an operating system that allowed machines to run many different programs at once with a central program that monitored and coordinated the computer's memory . Fairchild Camera and Instrument Corp. built the first standard metal oxide semiconductor product for data processing applications, an eight-bit arithmetic unit and accumulator. The fundamental components of this semiconductor laid the groundwork for the future discovery of the microprocessor in 1971. Another company that took advantage of the third generation advancements was IBM with the unveiling of the IBM System/360. The company was making a transition from discrete transistors to integrated circuits, and its major source of revenue moved from punched-card equipment to electronic computer systems.
UNIX : In 1969 AT&T Bell Laboratories programmers Kenneth Thompson and Dennis Ritchie developed the UNIX operating system on a spare DEC minicomputer. UNIX was the first modern operating system that provided a sound intermediary between software and hardware. The UNIX operating system quickly secured a wide following, particularly among engineers and scientists at universities and other computer science organizations.

FOURTH GENERATION
( 1971 – Present )

The microprocessor brought the fourth generation of computers, as thousands of integrated circuits we rebuilt onto a single silicon chip. After the invention of the integrated circuit, the next step in the computer design process was to reduce the overall size. Large scale integration (LSI) could fit hundreds of components onto one chip. By the 1980's, very large scale integration (VLSI) squeezed hundreds of thousands of components onto a chip. Ultra-large scale integration (ULSI) increased that number into the millions. The ability to fit so much onto an area about half the size of a U.S. dime helped diminish the size and price of computers. It also increased their power, efficiency and reliability. The Intel 4004 chip, developed in 1971, took the integrated circuit one step further by locating all the components of a computer (central processing unit, memory, and input and output controls) on a minute chip. Whereas previously the integrated circuit had had to be manufactured to fit a special purpose, now one microprocessor could be manufactured and then programmed to meet any number of demands. Soon everyday household items such as microwave ovens, television sets, and automobiles with electronic fuel injection incorporated microprocessors (Gersting 35 - 39). Such condensed power allowed everyday people to harness a computer's power. They were no longer developed exclusively for large business or government contracts. By the mid-1970's, computer manufacturers sought to bring computers to general consumers. These minicomputers came complete with user-friendly software packages that offered even non-technical users an array of applications, most popularly word processing and spreadsheet programs. Pioneers in this field were Commodore, Radio Shack and Apple Computers. In the early 1980's, arcade video games such as Pac Man and home video game systems such as the Atari 2600 ignited consumer interest for more sophisticated, programmable home computers. In 1981, IBM introduced its personal computer (PC) for use in the home, office and schools. The 1980's saw an expansion in computer use in all three arenas as clones of the IBM PC made the personal computer even more affordable. The number of personal computers in use more than doubled from 2 million in 1981 to 5.5 million in 1982. Ten years later, 65 million PCs were being used. Computers continued their trend toward a smaller size, working their way down from desktop to laptop computers to palmtop. In direct competition with IBM's PC was Apple's Macintosh line, introduced in 1984. Notable for its user-friendly design, the Macintosh offered an operating system that allowed users to move screen icons instead of typing instructions. Users controlled the screen cursor using a mouse, a device that mimicked the movement of one's hand on the computer screen. As computers became more widespread in the workplace, new ways to harness their potential developed. As smaller computers became more powerful, they could be linked together, or networked, to share memory space, software, information and communicate with each other. As opposed to a mainframe computer, which was one powerful computer that shared time with many terminals for many applications, networked computers allowed individual computers to form electronic gateways. Using either direct wiring, called a Local Area Network (LAN), or telephone lines, these networks could reach enormous proportions. A global web of computer circuitry, the Internet, for example, links computers worldwide into a single network of information. During the 1992 U.S. presidential election, vice-presidential candidate Al Gore promised to make the development of this so-called "information superhighway" an administrative priority. The ideals expressed by Gore and others are in usage everyday through email, web browsing, and e-commerce.
As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUI's, the mouse and handheld devices. A new generation of computers will emerge with the use wireless communications and wide area networking.

FIFTH GENERATION
( PRESENT & BEYOND )
Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. Artificial Intelligence is the branch of computer science concerned with making computers behave like humans. The term was coined in 1956 by John McCarthy at the Massachusetts Institute of Technology.
They will be able to take commands in an audio visual way and carry out instructions. Many of the operations which requires low human intelligence will be performed by these computers Artificial intelligence includes
 Expert Systems: programming computers to make decisions in real-life situations (for example, some expert systems help doctors diagnose diseases based on symptoms)

 Neural Networks: Systems that simulate intelligence by attempting to reproduce the types of physical connections that occur in animal brains

 Robotics: programming computers to see and hear and react to other sensory stimuli

 Natural Language: programming computers to understand natural human languages

 Games Playing: programming computers to play games such as chess and checkers
Currently, no computers exhibit full artificial intelligence. The greatest advances have occurred in the field of games playing. The best computer chess programs are now capable of beating humans. In May,1997, an IBM super-computer called Deep Blue defeated world chess champion Gary Kasparov in a chess match.
In the area of robotics, computers are now widely used in assembly plants, but they are capable only of very limited tasks. Robots have great difficulty identifying objects based on appearance or feel, and they still move and handle objects clumsily.
Today, the hottest area of artificial intelligence is neural networks, which are proving successful in an umber of disciplines such as voice recognition and natural-language processing. There are several programming languages that are known as AI languages because they are used almost exclusively for AI applications.