Computer? What’s a computer? .

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Computer? What’s a computer?
Until the 1930s a “computer” was a
person who did mathematical
calculations.
This changed at least in part due to
World War II -The US, Great Britain and Germany
all had active research into computer
technology.
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
Man vs. Machine
Albert Einstein said:
Computers are incredibly fast, accurate,
and stupid:
Humans are incredibly slow, inaccurate
and brilliant;
Together they are powerful beyond
imagination.1 -- Albert Einstein
www.quotiki.com
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
We have desktop
computers.
Like this system at
www.dell.com
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
We have laptop computers
Apple
Dell
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
There are full
computers that
weigh little.
 Sony Vaio
Others are built to be
essentially
indestructible.
 Panasonic
ToughBook
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
 And there are supercomputers.
.
Cray Inc
www.cray.com
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
The one laptop per child non-profit initiative!
“The mission of One Laptop per Child (OLPC) is to empower
the children of developing countries to learn by providing
one connected laptop to every school-age child.”
http://www.laptopgiving.org
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
 Much of what we own, use and do contains
computers.
 A computer on the “inside” of a device designed to
do something else is an embedded computer.
 Cars
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–
Antilock break systems
All wheel drive system
GPS systems
Satellite radio
Garmin 750
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
 There are digital calculators
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer
 PDA – Personal Digital Assistant
Palm TX Handheld
HP iPAQ Moble
Messenger
Blackberry 8703e
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
 Music Machines
Centon MP3 Player
PowerUp MP3 Player
Alexa MP3/MP4
Player
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
 Music Machines -- iPods
Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
Then there are computers in
Deep Fryers
Microwave Ovens
Alarm Clocks
Cameras
Augmentative Communication Devices
(Talkers)
 Cash registers
 Gasoline pumps
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Copyright © 2008 by Helene G. Kershner
Computer? What’s a computer?
And then there are cell phones? Or are these
PDAs, cameras, alarm clocks, time pieces and…
computers
Copyright © 2008 by Helene G. Kershner
Computers, Where did they come from?
Computer = Person
 Devices to assist people with their calculations
Mechanical Age
 5000 BC
Still in use in Asia
 1621
Slide rule – William Oughtred
Copyright © 2008 by Helene G. Kershner
Computers, Where did they come from?
Mechanical Devices

1642 -- Blaise Pascal invented the first machine like
adding machine (added and subtracted)
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Used gears or wheels that were moved with a pointed object
Legend – he built if for his father who was a tax collector and
spent lots of time and effort adding and subtracting
1673 -- Baron Gottried Wilhelm von Leibnitz
redesigned Pascal’s device so it could multiply and
divide.
Copyright © 2008 by Helene G. Kershner
Computers, Where did they come from?
Mechanical Devices
 1833 – Charles Babbage an eccentric British
mathematician and inventor created a mechanical
machine that would perform many of the functions of
modern computers
 It was never built. The precision required for the
gear systems was beyond the capabilities of the day.
 Using more modern Engineering
techniques his son was able to
create a model an prove that it
would work.
Copyright © 2008 by Helene G. Kershner
Computers, Where did they come from?
The Industrial Age – mid 1800s through early 1900s
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Herman Hollerith’s Tabulating machine
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Agrarian world  Industrialization
Farms  factories
Cloth made by hand  textile industries (mechanical loom)
Animal power  steam  internal combustion engine
Gas lights  electric lights
Contest to calculate the 1900 census
“Grandparent” company of IBM
1888 – William Burroughs’ created & patented a paper
tape adding machine

Burroughs Corp. moved from adding machines to computers
in 1961.
Copyright © 2008 by Helene G. Kershner
Burroughs Adding Machines
Early Burroughs
adding machine
1925 advertisement
1950 era Burroughs
adding machine
Photos found on eBay
Copyright © 2008 by Helene G. Kershner
Computers, Where did they come from?
Next major step: late 1930

What was happening in the world in the late 1930s?
Great Britian
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COLOSSUS -- 1943
Single Purpose Computer – code breaker
www.codesandciphers.org.uk/lorenz/colossus.htm
Copyright © 2008 by Helene G. Kershner
Computers, Great Ideas
 In 1936, mathematician Alan Turing theorized
that a general purpose computer could be built.
 Great Idea – He asked, what is computable? He
then suggested that “a task is computable if one
can specify a sequence of instructions which when
followed will result in the completion of the task.” *
 This was intended strictly as a mathematical idea.
This concept/thought experiment is known as a
Turing machine.
 In 1943, Turing helped the British government
develop COLOSSUS.
*plato.stanford.edu/entries/turing-machine/
Copyright © 2008 by Helene G. Kershner
Computers, Great Ideas
 In 1944, scientist John Von Neumann added
his talents to the ENIAC team.
 Great Idea -- Developed the concept of
storing a program in the computer’s memory,
rather part of it’s circuitry.
 This is called the stored program concept.
 Each program was a numeric code using binary
digits (0 or 1) (off or on).
 Both the program and the data could now be
stored in memory.
Kershner, Computer Literacy 3rd Ed.
Copyright © 2008 by Helene G. Kershner
Computers, Where did they come from?
Next major step: late 1930
What was happening in the world in the late 1930s?
Telephone switches vs Vacuum Tubes
Harvard/IBM – Howard Aikens
1943
www-03.ibm.com/ibm/history/exhibits/markI/markI_intro.html
Univ. of Pennsylvania- John Mauchly &
Presper Eckert
1946
en.wikipedia.org/wiki/ENIAC
Copyright © 2008 by Helene G. Kershner
History
Computer Generations
Each Generation notes a major change in
technology.
 First Generation (1951 – 1958)
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Vacuum tube technology
Punched card or magnetic tape
Machine language
Magnetic core
 Second Generation (1959 – 1964)
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Great Idea -- Transistor
Solid-state technology – no moving parts
Punched card or magnetic tape
Assembly language or higher level language
Magnetic core
Copyright © 2008 by Helene G. Kershner
Computers, Where did they come from?
Vacuum Tubes
Transistors

en.wikipedia.org/wiki/Vacuum_tubes
Schindler, Kris
Copyright © 2008 by Helene G. Kershner
History
Computer Generations
 Third Generation (1965 – early 1970s)
 Great Idea -- Integrated circuits (IC) – multiple
transistors on a chip
 Silicon chips
 Large-scale integration
 Punched cards, magnetic tape, magnetic disks
 Magnetic core, some semiconductor memory
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Fourth Generation Computers (early 1970s – present?)
Very large-scale integration (VLSI)
Great Idea– Computer on a chip - Microprocessor chip
Magnetic disks, floppy disks, flash/memory sticks
Great Idea – High level programming language“ --user
friendly” software
 Semiconductor memory
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Copyright © 2008 by Helene G. Kershner
Computers, Where did they come
from?
Integrated Circuits (IC)
Very large-scale integrated
circuits (VLSI)

Schindler, Kris
Copyright © 2008 by Helene G. Kershner
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