CS 104 Introduction to Computer Science and Graphics Problems History of Computer 09/05/2008 Yang Song (Prepared by Yang Song and Suresh Solaimuthu)

What is a Computer? Computer is a machine that manipulates data according to a list of instructions (Wikipedia) Computer is an electronic device.... Computer can compute…. Compute means calculate Calculate means adding

Characteristics of a Computer Speed Accuracy Diligence Versatility Storage IQ? Feeling?

History of Computing Devices Abacus Napier’s Bones Slide Rule Pascal’s Machine Leibniz’s Machine Babbage’s Analytical Engine Mechanical and Electrical Calculator Modern Electronic Calculator Digital Computer

Abacus An abacus is a calculating tool for arithmetic processes, constructed as a frame with beads sliding on rods. It has been used for tens of centuries, around the world.

Napier’s Bones John Napier created and published it in For calculation of products and quotients. An example of multiplication (Picture from wikipedia)

Slide Rule A mechanical analog computing device, generally consisting of at least two finely divided scales (rules), most often a fixed outer pair and a movable inner one, with a sliding window called “cursor”. It is used primarily for multiplication and division. Widely used in engineering and science till 1970s.

Pascal’s Machine Blaise Pascal invented it in 1645, could do addition and subtraction.

Leibniz’s Machine Gottfried Leibniz developed Pascal’s idea and constructed this calculating machine in It was therefore the first calculator which could handle the four rules of arithmetic.

Babbage’s Analytical Engine In 1823 Charles Babbage built a mechanical machine to do complex mathematical calculations called difference engine. Later he developed a general-purpose calculating machine called analytical engine It was intended to use loops of punched cards to control and automatic calculator, which could make decisions based on the results of previous computations. Charles Babbage is called the father of computers, his assistant, Ada Lovelace, is called the first programmer.

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Computer Generations The history of computer development is known as computer generations. John von Neumann and his Neumann architecture: using a processing unit and a single separate storage structure to hold both instructions and data. Each generation of computer is characterized by a major technological development that fundamentally changed the ways the computers operate. This resulted in smaller, cheaper, powerful, efficient and reliable machines. How many generations of computers we have now?

First Generation 1940s~1956 Vacuum Tubes Used vacuum tubes for circuitry and magnetic drums for memory Often enormous, taking up entire rooms Reliability is a problem Expensive, used lots of electricity, generated lots of heat Examples: ENIAC-Electronic Numerical Integrator and Calculator UNIVAC-UNIVersal Automatic Computer

ENIAC: the first high-speed, purely electronic, Turing- complete, digital computer capable of being reprogrammed to solve a full range of computing problems. It contained 17,468 vacuum tubes, 7,200 crystal diodes, 1,500 relays, 70,000 resistors, 10,000 capacitors and 5 million hand-soldered joints. 27 Tons, 8.5ft X 3ft X 80ft.

Second Generation Transistors The transistor was far superior to the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy-efficient and more reliable than their first- generation predecessors Still the transistors generated lots of heat High level programming languages were used like COBOL and FORTRAN Examples: IBM 1620, CDC 3600

The IBM 1620 Data Processing System Nick name: CADET (Can't Add Doesn't Even Try)

Third Generation Integrated Circuits (IC). Up to 100 devices per chip. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system CPL->BCPL->B Examples: IBM-360, ICL-1900, VAX-750

VAX Could handle up to 16 terminals. In 1980s, it would cost 100,000 USD.

Fourth Generation 1971-present Microprocessors Very Large Scale (VLSI), Ultra Large Scale (ULSC), millions of components could be fit into a single silicon chip Due to the development of microprocessor it is possible to place computer's central processing unit (CPU) on single chip 1981: IBM PC, 1984: Apple Macintosh GUIs, Mouse….

Fifth Generation Present and Beyond Based on artificial intelligence, the fifth generation is still in development, though there are some applications, such as voice recognition, that are being used today The use of parallel processing and superconductors is helping to make artificial intelligence a reality Quantum computation and molecular and nano technology will radically change the face of computers in years to come Any other idea?