1. Session One: An Introduction to Computing History of Computers1

2. An Introduction to Computing - Session One: History of Computers
First mechanical calculators
1623 – William Schickard built first mechanical calculator
1642 – the Pascaline by Blaise Pascal
1671 – Gottfried Wilhelm von Leibniz
Johannes Kepler revolutionized astronomy using design by Schickard
Leibniz’s work formed the basis of many calculators and designs; Leibniz also described the binary numeral system, a central ingredient to all modern computers; Up to 1940s, many designs based on decimal system
IBM developed punch card technology into a powerful tool for business data processing. By 1950, IBM card had become ubiquitous in industry and government
In many computer installations, punched cards were used until (and after) the end of the 1970s. For example, science and engineering students at many universities around the world would submit their programming assignments to the local computer centre in the form of a stack of cards, one card per program line, and then wait for the program to be queued for processing, compiled, and executed. In due course, a printout of any results, marked with the submitters identification, would be placed in an output tray outside the computer center. In many cases, results would comprise solely of a printout of error messages regarding program syntax etc, necessitating another edit-compile-run cycle.
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3. An Introduction to Computing - Session One: History of Computers
1801: Punch card technology
Joseph-Marie Jacquard developed loom in which pattern woven controlled by punch cards
1833: Charles Babbage began designing an analytical engine based on punch cards for programming
1890 – US Census Board used punch cards and sorting machines designed by Herman Hollerith to handle data from decennial census
Hollerith’s company eventually became the core of IBM
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4. An Introduction to Computing - Session One: History of Computers
s: First programmable machines
1835 – Babbage described analytical machine
Analytical machine was to be a general-purpose programmable computer, using punch cards for input and a steam engine for power, and utilizing gears for the function served by the beads of an abacus
Anita C/VII used a tube display and 177 subminiature thyratron tubes
‘Computer’ – job title assigned to people who used calculators to perform mathematical calculation
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5. An Introduction to Computing - Session One: History of Computers
1930s-1960s: Desktop calculators
1930s – Desktop calculators able to add, subtract, multiply, divide
1948 – the Curta; small, portable mechanical calculatir approx. size of pepper grinder
1961 – first electronic desktop calculator considered to be by Sumlock Comptometer (Anita C/VII)
1963 – four-function EC-130 with 13-digit capacity; $2200
1965 – LOCI-2 by Wang Laboratories
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6. An Introduction to Computing - Session One: History of Computers
Pre-1940: Analog computers
Used continuously varying amounts of physical quantities (voltages, currents, rotational speed of shafts) to represent quantities being processed
Not very flexible and needed to be reconfigured/reprogrammed manually to switch from one problem to another
Most widely developed used for aiming weapons; e.g: Norden bombsight and artillery aiming for battleships
Norden stayed in use for decades after WWII
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7. An Introduction to Computing - Session One: History of Computers
1940s and early 1950s: First electrical digital computers (First Generation)
Electronic circuits, relays, capacitors, vacuum tubes replaced mechanical equivalents; by 1954, magnetic core memory replacing most other forms of temporary storage
1940 – first computing machine used remotely over phone line
1945 – US-built ENIAC 1,000 times faster than contemporaries
Colossus was first totally electronic computing device
1941 – Z3 by Konrad Zuse becaome first functional program-controlled computer
First remote phone line comp - George Stibitz, September 11
To program ENIAC meant to rewire it however
Colossus had paper-tape input and was capable of being configured to perform a variety of boolean logical operations on its data; used to break German ciphers during World War II by the British
Colossus source –
Z3 replaced decimal system with binary system; Z3 easier to rebuild and potentially more reliable
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8. An Introduction to Computing - Session One: History of Computers
1940s and early 1950s: First electrical digital computers (First Generation)
1947 – invention of transistor to replace valves
1950 – MESM(Malaya elesktron schetnaya mashina) became operational
1951 – LEO I(lyons electronic office) ran the world’s first regular routine office computer job
1951 – UNIVAC was the first ‘massed produced’ computer; 46 machines sold at more than US$1 million each
– FORTRAN developed and released
1955 – microprogramming invented by Maurice Wilkes
1956 – IBM sold its first magnetic disk system (RAMAC: Random Access Method of Accounting and Control)
FORTRAN was first implemented high-level general purpose programming language developed at IBM
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9. An Introduction to Computing - Session One: History of Computers
Late 1950s and early 1960s: Second Generation
Transistorized computers normally referred to as Second Generation
Computers became smaller – IBM 1620 was size of office desk, as opposed to IBM 650 which weighed over 900kg with power supply of 1350kv, both held in separate cabinets of approx. 1.5 metres by 0.9 metres by 1.8 metres
Second generation computers still expensive however
Mainly used by universities, governments and large corporations
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10. An Introduction to Computing - Session One: History of Computers
Late 1950s and early 1960s: Second Generation
1959 – 12,000 medium scale IBM 1401 shipped; most successful machine in computer history at the time
1960 – 2,000 IBM 1620; smaller, transistor based
1960 – DEC launched the PDP-1 to be used by technical staff in labs and for research
1961 – first dual processor and virtual memory computer released (B5000)
1962 – IBM S/360 series able to run same software at different combinations of speed, capacity and price
PDP-1 – stack architecture, descriptor-based addressing, and no programming directly in assembly language
S/360 series also pioneered commercial use of microprograms, and extended instructions et for processing many types of data
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11. An Introduction to Computing - Session One: History of Computers
Post-1960: Third Generation and beyond
Use of computers became more popular
Invention of microchip (integrated circuit) by Jack St. Clair
Microchip later led to invention of microprocessor at Intel
1970 – Microprocessor led to development of small, low-cost computers for ownership by individuals and small businesses (microcomputer)
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12. An Introduction to Computing - Session One: History of Computers
Timeline
cfm?action=time&chapter=home
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13. An Introduction to Computing - Session One: History of Computers
Links
References
uter
Of Interest
sus.html
ks/papers/133.pdf
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14. An Introduction to Computing - Session One: History of Computers
Assignment
Go through the online Timeline as referenced on the relevant slide
Together with these slides, develop a general understanding of the steps that brought us to current day levels of computing
Be ready to discuss in class
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15. An Introduction to Computing - Session One: History of Computers
THANK YOU
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