3rd Class

        Third Generation Computers (1966-75)       Third generation computers were introduced in 1964. These computers used a new technology of integrated transistor circuits better known as IC or Integrated Circuits that were made of electric wires. Instead of having one transistor working separately, several transistors would be integrated with other components and sealed in a small package called IC (Integrated Circuit.) or the Chip. These computers had much higher speeds, larger storage capacities and lower prices. Examples of 3rd generation computers were IBM 360/370 and NCR 395, IBM-360 series, ICL-2900 series, KL 2903, CDC-1700. The other main feature of the 3rd generation computers was that the size of main memory was increased and reached about 4 megabytes. The computers of this generation were relatively inexpensive and faster, more durable and reliable. They used high level languages such as FORTRAN and more...

The Second Generation Computers (1956-65)   In 1947, three scientists, John Bardeen, William Shockley and Walter Brattain working at AT&T's Bell Labs invented the transistor which functioned like a vacuum tube. The transistor was faster, more reliable, smaller and much cheaper to build than a vacuum tube. One transistor replaced the equivalent of 40 vacuum tubes. The use of this machine marked a new beginning for the computer. The development of the transistor was soon applied to computers which reduced their size, the power requirement and increased their processing speed. Some models of the second generation computers are IBM 1401, IBM 1620, IBM 7094 and UNIVAC 1108. IBM-700, 1401 and ATLAS. (See Figure 3.2.4)         The main feature of the second generation computers was that the computers of this generation replaced vacuum tubes with transistors. Magnetic cores and different magnetic more...

     The First Generation Computers (1949-55)     The first generation computers were huge, slow, expensive and often undependable. In 1946, two Americans, Prosper Eckert and John Mauchly built the ENIAC electronic computer which used very large and heavy electronic vacuum tubes, which took up a lot of space and gave off a great deal of heat like the light bulbs. The ENIAC led to other vacuum tube type computers like the EDVAC (Electronic Discrete Variable Automatic Computer) and UNIVAC I (Universal Automatic Computer). They also used the concept of stored program. These computers were 5000 times faster than the MARK-1, which is considered to be the first electromechanical machine. These computers' used machine language for giving instructions.             Limitations: Since first generation computer is a more...

          Generation of Computers   A generation refers to the state of improvement in the development of a product. This term is also used in the different advancements of computer technology. Each phase of computer development is known as a separate generation of computers. With each new generation, the computer has become smaller and more advanced than the previous generation before it. The computer can be classified into five generations according to their types of electronic circuits such as vacuum tube, transistor, 1C (Integrated Circuits), etc. Let us learn about these different generations of the computer one by one.  

      Introduction       Just as we humans have different generations, so does the computer. In our family we have different generations such as: Grandparents  Parents  Children             Similarly, the computer can also be classified into different generations.  

      Difference Engine     This was an early calculator designed by Charles Babbage. The difference engine was made to calculate various mathematical functions and mathematical tables. This project was started in 1821 and it employed wheels and rods but failed its test in 1833 because the technology at that time was not so developed. Accurate parts of this engine could not be made and Babbage had to leave his project after spending a huge amount. Although it was never completed, it improved the precision of Britain's machine-tool industry. (See Figure 3.1.7)                                                      Difference engine was designed more...

     An Electro- Mechanical Computer- Mark - I        Mark - 1 was probably the last electro mechanical computer which was invented by Prof. Howard Aiken in the U.S.A. Mark-1 was constructed in 1943. The main advantage of the Mark I was that it was fully automatic?it did not need any human intervention once it started. It was the first fully automatic computer to be completed. It was also more reliable than the early electronic computers. This machine was capable to multiply two 10- digit numbers in 5 seconds. It was the first machine, which could perform according to pre-programming. It was also known as ASCC (Automatic Sequence Controlled Computer). Mark-1 is considered to be' the beginning of the era of the modern computer' and 'the real dawn of the computer age'.     more...

        Hollerith's Machine     Herman Hollerith was an American statistician who developed a mechanical tabulator based on punched cards to rapidly tabulate statistics from millions of pieces of data. It was a tabulating machine which could count quickly.  It was the first automatic data processing system. The tabulating machine was an electrical device which assisted in summarizing information and accounting. This machine was developed in 1887. The machine was developed to help process data for the 1890 U.S. census. It was the first electromechanical punched card tabulator. He used punched cards for input, output and instructions. This machine was used by American Department of Census to compile their 1890 census data. The system used a hand punch to record the data as holes in dollar-bill-sized punch cards and a tabulating machine to count them. Hollerith's Machine completed the compilation of census more...

      Analytical Engine     The analytical engine was an important step in the history of computers. It was an automatic machine that used to have all the features of the modern computer. It was the design of a mechanical general-purpose computer by the British mathematician Charles Babbage. He started designing it in 1833. Babbage continued to refine the design until his death in 1871. In its design, this machine could perform all the four mathematical operations as well as some logical operations. Babbage established the basic principles on the basis of which, today's computers work. He included the concept of control processor, storage area and input-output devices in design. It had almost all the parts of a modern computer in design. Because of the complexity of the machine, the lack of project management science, the expense of its construction and the difficulty more...

     Punch Card in- Jacquard's Loom     The Jacquard loom is a mechanical loom, invented by Joseph Marie Jacquard in 1801 that simplifies the process of manufacturing textiles with complex patterns. The loom is controlled by punched cards with punched holes, each row of which corresponds to one row of the design. Multiple rows of holes are punched on each card and the many cards that compose the design of the textile are strung together in order. Its entire operation was under the control of a program and its weaving process was automatic. The Jacquard loom was the first machine to use punched cards to control a sequence of operations. Although it did no computation based on them, it is considered an important step in the history of computing hardware. With the invention of punched cards, the era of storing and retrieving information more...