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Oct 22, 2014
Computer Computer comes from the word Compute which means to calculate Calculating Device which can be perform arithmetic operation with speed Fast Calculating Machine Non-mathematical & Non- numerical Computer can store, process& retrieve data when desired Data Processor
CHARACTERISTICS OF COMPUTERS Speed
Accuracy Diligence :- tiredness Versatility :- Multitasking, (e.g. result, CV, Software Development) Power of remembering
No I.Q NO Feeling
THE HISTORY OF COMPUTERS Computers as we know are very relatively new devices. This presentation shows the progression from primitive mechanical calculators to modern PCs. The history of computers is commonly divided into generations.
GENERATION 0 :MECHANICAL COMPUTERS (1642-1945) The first computing devices were invented during this period. The German inventor Wilhelm Schickard (15921635) built the first working calculator in 1623 (on fire). 1642 the french scientist Blaise Pascal (1623-1662) built a mechanical calculator which only
can add or subtract.
GENERATION 0 :MECHANICAL COMPUTERS (1642-1945) Pascals Calculator
GENERATION 0 :MECHANICAL COMPUTERS (1642-1945) PROGRAMMABLE DEVICES
Jacquards loom 1801 The Frenchman Joseph-Marie Jacquard (1752-1834) invented a programmable loom, in which removable punch cards were used to represent patterns.
Jacquard loom
It was not until the beginning of the 19th century (1800s) that the ideas automatic computing machines began to evolve. The first was developed by a French textile manufacturer called Joseph Jacquard. He invented a punch card system for programming the designs on a carpet making loom. First he used single cards to control the pattern of the threads. On later machines the cards were joined together to form repeating patterns. This idea of punch cards was adopted for use with musical instruments, such as the barrel organ. Here a sequence of valves were opened and closed controlling air flow into various organ pipes. Tunes could be programmed and loaded into the machine.
History of Computers - Long, Long Ago
beads on rods to count and calculate still widely used in Asia!
History of Computers - Way Back When
Slide Rule 1630
based on Napiers rules for logarithms used until 1970s
History of Computers - 19th Century
first stored program metal cards first computer manufacturing still in use today!
Charles Babbage - 1792-1871 Difference Engine c.1822 huge calculator, never finished
Analytical Engine 1833 could store numbers calculating mill used punched metal cards for instructions powered by steam! accurate to six decimal places
BABBAGE difference engine
In the 1820s Charles Babbage designed a mechanical machine called the Difference engine. The purpose of this machine was to calculate and print out tables for the Admiralty. (ie, tides, tables and planetary positions for navigation). The machine consisted of cog wheels that could be set in keyed positions, these turned as the computations were performed. Due to the limitations of mechanical engineering in this period, and lack of money, the machine was never completed.
BABBAGES analytical engineA mechanical computer that can solve any mathematical problem. It used punch-cards similar to those used by the Jacquard loom and can perform simple conditional operations.
Babbage laid down the foundations for modern computing. He stated that an automatic computing machine must have:1) 2) A store for the numbers, we now call this memory. A device for performing arithmetic operations, he called this a mill, we now call this the arithmetic unit or central processor unit (CPU). 3) A device for causing the operations of the machine, for example transferring numbers from one place to another. This is now referred to as the control unit. 4) An input and output device. Such as card reader or printer. Today this would also include screen, mouse and keyboard.
THE MARK I COMPUTER(1937-44)Howord A. Aikan of Harvard University & I.B.M. designed first fully automatic calculating Machine Size of computer is 50 feet long 8 feet high 23 decimal digits can be used in the machine
THE ATANSOFF BERRY COMPUTER (1939-42)Dr. John Atanasoff was developed Electronic Machine for mathematical equations
Atansoff Berry Computer or ABC45 vacuum tubes for internal logic & capacitors for storage
THE MARK I COMPUTER(1937-44)
THE ATANSOFF BERRY COMPUTER
HARVARD MARK I and IIThe modern computer era commenced with the first large-scale automatic digital computer, which was developed between 1939 and 1944. The Harvard Mark I and II was the invention of Howard Aiken. The machines were constructed out of switches, relays and rotating shafts.
In 1945, LTJG Grace Murray was working on the Harvard University Mark II Aiken Relay Calculator. While testing Mark II due to a malfunction, a moth was found trapped between the points of a Relay. The operators removed and affixed the moth to the computer log, with the entry: "First actual case of bug being found." They put out the word that they had "debugged" the machine, thus introducing the term "debugging a computer program."
THE ENIAC(1943-46)THE ELECTRONIC NUMERICAL INTEGRATED AND CALCULATOR In U.S.A. at Moor School of Engineering of University of Pennsylvania team of Prf. J. Presper & John Machly constructed an electronic computer Result of military need 20 x 40 sq. ft. room & 18,000 Vacuum Tubes Limited amount information ,
Difficult to detect the errors & change the programme
THE EDVAC(1946-52)THE ELECTRONIC DISCRETE VARIABLE AUTOMATIC COMPUTER Stored Program Developed by Dr. John Von Neumann
Binary System
THE ENIAC(1943-46)
THE EDVAC(1946-52)
THE EDSAC (1947-49)THE ELECTRONIC DELAY STORAGE AUTOMATIC CALCULTOR May 1949(Britisher) Developed by group of scientists headed by Pof. Maurice Wilkes at Cambridge University Add 1500 mic. Sec. Mult. 4000 mic. sec
MANCHESTER MARK -I(1948)Storage PurposeDesigned Prof. Neumann & Scientists. of Manchester University Group 32 words 31 digit
THE EDSAC
THE UNIVAC (1951)THE UNIVERSAL AUTOMATIC COMPUTER
In 1951 ( Digital Computer)Census Bureau
701 Commercial Computer (IBM )
UNIVAC - 1951 first fully electronic digital computer built in the U.S. Created at the University of Pennsylvania ENIAC weighed 30 tons
contained 18,000 vacuum tubes Cost a paltry $487,000
THE UNIVAC
GENERATION 1 :VACUUM TUBES (1945-1954) 1940s Computers designers began to replace electromagnetic relays with Vacuum tubes, small glass tubes from which all or most of the gas has been removed. Since vacuum tubes have no moving parts, they enable switching of electrical signals at speeds far exceeding those of relays.
GENERATION 1 :VACUUM TUBES (1945-1954) Computing and World War II COLOSSUS With the ideas of Alan Turing (1912-1954), the British Government built the first electronic computer COLOSUS, to decode encrypted Nazi comunications. Its contained more than 2300 vacuum tubes.
GENERATION 1 :VACUUM TUBES (1945-1954) ENIAC Since Colossus was classified, the first publicly known electronic computer was ENIAC (1946),developed at USA to compute ballistics tables for the US army. Consisted of 18000 vacuum tubes. It was less advanced than its predecessors but could perform more complex calculations than the Mark I could and operated up to 500 times faster. Another advantage of Eniac was that it was programmable.
GENERATION 1 :VACUUM TUBES (1945-1954)
GENERATION 1 :VACUUM TUBES (1945-1954) The von Neumann Architecture John Von Neumann (1903-1957), was a scientist involved in the Eniac project. He design an alternative computer architecture in which programs could be stored in memory along with data. He also introduced the used of binary representation (base 2 0,1).
COMPUTER GENRATIONSFIRST GENERATION (1942-1955)Vacuum Tube ,
ENIAC, EDVAC, EDSACADVANTAGES Electronic Components Electronic digital Computer Fastest Calculating Device DISADVANTAGES Bulky in Size , Unreliable, Large amount of heat
Air conditioning requiredHardware failures Maintenance required Manual assembly , Commercial production was difficult & Costly
Second Generation 19651963 1956 Computers began to incorporate Transistors Replaced vacuum tubes with Transistors
First Transistor Uses Silicon
developed in 1948 won a Nobel prize
on-off switch Second Generation Computers used Transistors, starting in 1956
GENERATION 2 :TRANSISTORS (1954-1963) Transistors are pieces of silicon whose conductivity can be turned on and off using an electric current. Since transistors were smaller, cheaper and more energy-efficient than vacuum tubes, they allowed for the production of more powerful yet inexpensive computers. IBM began marketing transistor-based computers to private businesses. They introduced the first high-level programming language (FORTRAN), with a higher level of abstraction and simplifying the task of programming.
LISP, BASIC, COBOL.
SECOND GENERATION (1955-1964)ADVANTAGES Smaller in size Reliable, Less amount of heat Hardware failures are less Commercial use DISADVANTAGES Air conditioning required Maintenance required Manual assembly , Commercial production was difficult & Costly
Third Generation 1964-1971 1964-1971 Integrated Circuit Operating System Getting smaller, cheaper
Integrated Circuits
Third Generation Computers used Integrated Circuits (chips). Integrated Circuits are transistors, resistors, and capacitors integrated together into a single chip
Operating System Software Instructions for Computer Op