Generation of Computer

Generation of computer

The computer has evolved as a result of human’s search for fast, accurate calculating devices. However, the birth of digital computers depends upon many other inventions. Generations of computer are designed based on the new technological development which results in better, cheaper and small sized computers which are more robust, faster and efficient than the previous ones. There are five generations of computer. Generations of computer vary on the basis of:

• Technology used- include software and hardware
• computing characteristics
• physical appearance

First Generation (1940-1956)

Vacuum tubes in their circuits and magnetic drums for memory were used in this generation of computer. They were very large in size, taking up entire rooms. The instructions were written in machine languages which use binary code (0's and 1's). They were very costly to operate, consume a great deal of electricity and generate a lot of heat. This was often the cause of crash or breakdowns. Computers relied on machine language which is understood by computers to perform operations, and they were capable of solving one problem at a time. Input was totally given by punched cards as well as paper tape. Output was displayed on printouts. UNIVAC (Universal Automatic Computer), ENIAC (Electronic Numerical Integrator and Calculator), and EDVAC (Electronic Discrete Variable Automatic Computer) are the examples of computing devices used in first generation. First generation computers were used for scientific purposes or applications as they were the fastest computing device of their time.

Second Generation (1956-1963)

Transistors were replaced by vacuum tubes in the second generation of computers. The transistor was far superior to the vacuum tube and they allowed computers to become smaller, faster, cheaper, more energy-efficient and more reliable than the first-generation computers. Second-generation computers still used punched cards for input and printouts for output. The second generation’s computer used magnetic core technology for primary memory. Second-generation computers moved from confusing binary machine language to symbolic, or assembly languages that allowed programmers to specify instructions in words format. High-level programming languages such as early versions of COBOL and FORTRAN were also being developed at this time. These were also the first computers that stored their instructions in magnetic core technology. The first computers of this generation were invented for the atomic energy industry.The computation time was in microseconds.The cost of commercial production of these computers was very high but less than the first generation computers. The transistors had to be assembled manually in second generation computers. Examples: languageswerePDP-8, IBM 1401 and CDC 1604.

Third Generation (1964-1971): Integrated Circuits

The development of the integrated circuit was the characteristic of the third generation of computers. Transistors were miniaturized and settled on silicon chips known as semiconductors, which drastically increased the speed and efficiency of computers. Rather than punched cards and printouts, users had interacted with third generation computers through keyboards and monitors and incorporated with an operating system, that permitted the device to run many various applications at one time with a central program. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessor languages were used extensively for programming. The computation time was measured in nanoseconds. The size of these computers was decreased (i.e. small) compared to the second generation computers. Examples: IBM 370, PDP 11. The third generation computers consumed less power as well as they generated less heat compared to the second generation computers. The cost of the computer reduced knowingly. The maintenance cost of the computers was also less compared to their predecessors.

Fourth Generation (1971-Present):

The microprocessor was introduced by the fourth generation of computers since thousands of integrated circuits were built onto a single silicon chip. Components in the first generation filled an entire room could now fit in the palm of the hand. IBM introduced its first computer for the home user, and Apple introduced the Macintosh. Microprocessors also moved out of the kingdom of desktop computers and into many areas of life as more and more everyday products began to use microprocessors. Being more powerful, they could be linked together to form networks, which in the long run led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices.This generation of computers gave rise to Personal Computer (PC). Magnetic core memory was replaced by semi conductor memory resulting in fast random access to memory. Secondary storage device had become smaller in physical size and larger in capacity. This generation also brought the development of pointing devices like mouse, and handheld devices. Operating systems as MS-DOS and MS-Windows developed. This generation of computers braced Graphical User Interface(GUI). GUI is a user-friendly interface that allows user to interact with the computer through menus and icons. High-level programming languages are used. The computation time is in picoseconds. They are smaller. The fourth generation computers are also portable. They generate much lesser heat and require less maintenance compared to their previous generations. Networking has assisted in resource sharing and communication.

Fifth Generation (Present and Beyond)

Fifth generation computers hold artificial intelligence. They are still in development but some of the applications such as voice recognition are being used today. The fifth generation computers use super large scale integrated chips which are capable of storing millions of components on a single chip. These computers have huge memory requirements. They use parallel processingwhich allows various instructions to be performed in parallel rather than serial execution. Parallel processing leads to faster processing speed. Quantum computation and molecular and nanotechnology will be supported. The target of fifth-generation computing is to develop devices that respond to natural language.

Reference

Ghishing, Er.Ashim. Computer Science. Kathmandu, Nepal: Benchmark , 2008.