CSCI 1200

CSCI 1200

Julie Benoit

[email protected]

Introduction To Computing

Announcements : Labs

• start Monday.

• as of lunchtime, none were full.

• lots of space Wednesday.

• Thursday, teaching lab 2 (35).

• Mon, Thu & Wed teaching lab 1 (20).

Announcements : TAs

Huiqiong Chen • [email protected]• Tuesday & Wednesday

Franklin Fezeu • [email protected]• Monday & Thursday

Announcements : Quiz

• quiz each week.

• normally Thurs, announced otherwise.

• no quiz this week.

• quiz next week, material from today.

• 4 Multiple Choice & 2 Short Answer.

• no make-up quizzes, two lowest grades are dropped.

Announcements : Testing

Midterm :

• February 19th in class.

• 25 MC, 10 to 12 SA, matching question.

Exam :

• comprehensive.

• during the exam period.

History of Computing

• begins about 5000 years ago.

• earliest devices help with counting (commerce & inventory).

• early computing devices are NOT computers.

Motivation

• People have trouble :– remembering things.– doing calculations.– managing large volumes of data.– completing monotonous tasks.

Abacus

• memory aid.

• place value notation.

• trade increase.

• very fast.

Abacus

1946 - the abacus beats the mechanical calculator.

Private. T.N. Wood, the fastest mechanical calculator operator in the U.S. Army, used a contemporary state-of-the-art calculator, and was defeated in 4 out 5 speed competitions by Kiyoshi Matsuzaki, who used an abacus.

Pascal’s Calculator (1642)

• Blaise Pascal.• rotating gears.• addition & subtraction.• father was a tax collector.• no commercial success :

– expensive.– people worry jobs will be lost.– French currency not based on tens.

Leibniz’s Calculator (1694)

• like Pascal’s calculator - used gears & dials, but could also multiply.

• Leibniz studied Pascal's original notes & drawings, then improved on the design.

• 1820 before a full four function calculator (Colmar’s Arithometer) was developed - the Arithometer was widely used up until the First World War.

Jacquard Loom (1801)

• punched cards represent the pattern.• person needed much less skill and

training to operate a Jacquard loom. Luddites - when technologies like the Jacquard

Loom began replacing skilled craftsmen many became angry, and attempted to destroy the machines that put them out of work.

Difference Engine (1821)

• Charles Babbage.• a steam powered, fully automatic

machine for solving complex polynomial equations.

• not completed :– limitations of technology - problem of scale.– very difficult to work with.– interest in another project - Analytical

Engine.

Tabulating Machine (1890)

• Herman Hollerith.• data represented on punched cards.• cards are sorted based on the position

of the holes, data tabulated from the sorted cards.

• the 1890 US Census is completed in six weeks (rather than in ten years, or more).

Computer

• a computer is a general-purpose programmable machine.

• early computing devices :– could not be programmed.– were designed for a specific task.– are NOT computers.

Analytical Engine

• Babbage's real dream - build a general purpose programmable machine.

• vision not realizable in the 19th century.

• overall design, same as the modern computer - four smaller components.

Analytical Engine

• input - read in a list of instructions.

• processor - perform the instructions.

• memory - hold the results of intermediate calculations.

• output - print out the results.

Analytical Engine

• Babbage is considered the “father of the computer”.

• Ada Lovelace worked with Charles Babbage :– credited as the first programmer.– promoter of Babbage’s work.– programming language ADA, developed for

the United States Department of National Defense, named in her honour.

Computer

• a device, usually electronic, that processes data according to a set of instructions (Collins Concise English Dictionary).

• doesn’t matter how the device is constructed :– electrical, mechanical, optical.

First Computer?

John Atanasoff & Clifford Berry (1942) - ABC Computer built with vacuum tubes, solved equations containing 29 variables.

Howard Aiken & Grace Hopper (1944) - Mark 1, 55 feet long, 8 feet high, weighed 5 tons, contained nearly 760,000 separate parts, used by the US Navy for gunnery and ballistic calculations until 1959.

First Computer?

Konrad Zuse (1945) - Z3, world's first electronic, fully programmable computer, used old movie film to store programs and data.

John Eckert & John Mauchly (1946) – ENIAC, 1000 times faster than Mark I, constructed using 18,000 vacuum tubes, programmed by manually rewiring and resetting switches, ENIAC weighed 30 tons, a vacuum tube burnt out once every 15 minutes…

First Computer?

John Eckert & John Mauchly (1946) – …ENIAC used by the US military to do calculations for the design of the hydrogen bomb, weather prediction, cosmic-ray and random number studies, and wind-tunnel design.

First Computer?

John Eckert & John Mauchly (1946) – …ENIAC used by the US military to do calculations for the design of the hydrogen bomb, weather prediction, cosmic-ray and random number studies, and wind-tunnel design.

1st Generation

• 1940’s & 1950's.• vacuum tubes. • huge (30 x 50 feet), could use as much

energy as an entire city block of houses. • only used by government, military, & large

research organizations. • tedious - slow to program.• expected that the world will never need

more than a few dozen computers.

2st Generation

• late 1950's & 1960's.• constructed using transistors. • faster, smaller, more reliable. • programming languages like FORTRAN,

BASIC and COBOL are introduced - make programming easier.

• computers are opened up to more applications; airlines & small businesses can now afford them.

3rd Generation

• mid 1960's - 1970's.• constructed with integrated circuits -

smaller transistors and wires on silicone chips.

• miniaturization makes embedded computers possible; e.g. computers inside elevators, traffic lights and calculators.

4th Generation

• 1970's to present.

• constructed with VLSI - millions of transistors on a single silicone chip).

• single chip microprocessor.

• extreme miniaturization, very low costs.

• Apple Computers is founded in 1976, personal computers become a reality.