Abacus

• ~3000 B.C.• Beads for counting• Merchants used for

transactions

Pascal’s Pacaline

• 1642• Numerical wheel

calculator• Used by tax collector• 8 wheels with 10 notches• Wheel moves 10x to move

next wheel 1x• Wheels represent 1s, 10s,

100s, etc • Could only add

Leibniz’s Mechanical Multiplier

• 1694• Used gears and dials• Add and multiply

QuickTimeª and aTIFF (Uncompressed) decompressor

are needed to see this picture.

• Not until 1820 - mechanical calculator that could + - * /

Jacquard’s Loom

• 1820• Used punched cards• Controlled patterns to

be woven

Babbage’s Difference Engine

• 1822• Perform differential

equations• Powered by steam• Size of a steam engine• Could store a program• Worked on it for 10

yrs

Babbage’s Analytical Engine

• 1833• 1st general purpose

COMPUTER• 50,000 components• Size of a football field

Never constructed• Worked with Countess

of Lovelace - 1st programmer

Analytical Engine cont’d

• 4 machines:– Store (memory)

– Mill (computational unit

– Input (punch card reader

– Output - punched or printed

• The store capacity was 1000 words of 50 decimal digits used to hold variables and results.

• The mill could accept operands from the store, add, subtract, multiply or divide them, and return a result to the store.

Herman Hollerith

• 1886 - 1890• US census usually

took 10 yrs• Hollerith used

punched cards to store data and compiled data mechanically

• Census took 6 weeks• Started IBM

1st Electronic Computer

• 1940• John Atanasoff & C.

Berry• Used boolean algebra

to circuitry• True/False = On/Off• Lost funding ….

Atanasoff-Berry Computer

• the size of a desk, • weighed 700 pounds, • had over 300 vacuum tubes, • contained a mile of wire.• could calculate about one operation

every 15 seconds, • today a computer can calculate 150

billion operations in 15 seconds

1st Generation - 1945 - 56

• wwII = $$$• Zuse - cpu- r airplane design• Clossus decoded German

messages• Mark I inventor … “Only six

electronic digital computers would be required to satisfy the computing needs of the entire United States" Howard Aiken, 1947.

Mark I• 55 feet long x 8 feet high, 5-

ton• 760,000 separate pieces. • gunnery and ballistic

calculations• + - * /, 23 decimal places• Input: Pre-punched paper• Output: electric typewriter• Storage: mechanical wheels• Speed: 1 multiplication -->3-

5 seconds

Eckert’s ENIAC

• 1940s• Used 18000 vacuum

tubes• 160 Kilowatts• General purpose

computer• 1000x faster than

Mark I

ENIAC• $500,000• 167 square meters, 30

tons• 357 multiplications in 1

second• Input: card reader, re-

wiring - would take weeks• Output: printed• Speed : 357

multiplications in 1 second

John von Neuman’s EDVAC

• 1945• Stored memory• Stop and resume• Central processing

unit (CPU)• Commercially

available in 1951 as UNIVAC I

• Large and expensive

1st Generation Vacuum Tubes

• Unique operating instructions

• Different machine languages

• Difficult to program• Big, expensive, and

“buggy”• Magnetic drums for

storage

2nd Generation - 1956 - 63

• Used transistors• Smaller, faster, more

reliable• Not as warm• Assembly language

used

UNIVAC

• $1,000,000• Input: magnetic tape/

card reader• Output: tape, printer,

card• Speed: multiply time

of 1,800 microseconds

Commercial successes

• Bought by business, universities, and governments

• General Electric - payroll

• Used printers, tape and disk storage, memory, Operating systems, & stored programs

1952: UNIVAC ComputerUsed to Predict the 1952 US Election,

Walter Cronkite reading printer output, tape drives in background

Companies of the Day

• Burroughs• IBM• Sperry-Rand• Honeywell• Others ….

IBM 701 1952

Programming Languages

• Langauges gave cpu flexibility

• Stored programs• High level languages -

(COBOL, FORTRAN)• New career -->

programmer, anaylst, system experts….

3rd Generation 1964 - 71

• Transistor replaced with IC - Integrated circuit

• 3 components on a silicon disc

• Smaller, faster• OS allowed multi-

tasking

PDP-1

• $120, 000• OS allowed multi-

users• Spacewrs was first

game (2 player)

• Output: Cathode-Ray Tube

4th Generation 1971 - Present

• Large scale integration (LSI) 100 of components on a chip

• VLSI - 100,000 components

• ULSI - millions of components

• Increased power, efficiency, & reliability

Intel 4004 Chip

• 1971

• Microprocessor

• All parts (Cpu, memory, input and output controls) on a chip

• Multi-purpose - cars, fridges, microwaves, tv

• Made for general consumer

Companies of the day

• Radio Shack• Apple• Commodore• IBM• Atari (1980)

Applications of the Day

• Spreadsheet• Word Processors• Video Games• Pac-Man,

Visicalc - Apple 1979

IBM’s PC

• Personal computer• Home, office, school• 2 million in 81, 65

million in 92• Desktop - -> laptop• DOS … typed line

commands

Apple’s Macintosh

• 1984• Used mouse to move

or select icons … no typing

• 512 Kb of memory

Basic Parts of a Computer

PROCESSPROCESSINPUTINPUT OUTPUTOUTPUT

Hardware

• The physical parts of a computer.

• If you can touch it is hardware

Input Devices

• To get information into the processor

• Keyboard, mouse, scanner, touch screen, switches, camera, microphone, joystick ...

Output Devices

• Converts processed information into a form that can be used by/ aids humans

• Printer, monitor, speaker, switches,

Parts of the CPUCentral Processing Unit

INPUTINPUT OUTPUTOUTPUT

Arithmetic Logic Unit ALU

Arithmetic Logic Unit ALU

Control UnitControl Unit

Main Memory UnitMain Memory Unit

Central Processing Unit CPU

Arithmetic UnitALU

• Does all of the arithmetic and logic– Arithmetic : + - x /– Logic: = <>, < , > <=,

>=

• Computers convert everything to numbers and perform these operations….

Control Unit

• Controls the parts of the computer– Tells the printer when to

print– Tells the cpu that keys

are being pressed

• The Central Nervous System of the computer

Memory

• ROM– Read Only Memory

– The initial instructions to get the computer working.

– Cannot be erased.

– Not lost when power is off.

• RAM– Random access

memory.

– Where application and data are stored while being used.

– Can be changed.

– Lost when power is off.

Software

• The information (instructions or data) that the computer processes

• Stored on hardware• Loaded into RAM

when used.• More RAM = more

applications, larger documents,

Three Classifications of Software

• Operating System: the instructions that run the computer (DOS, Windows, Mac OS, Linux, …)

• Applications… the programs that allow you to do specific activities (wp, ss, games, …)

• Data - the information that is being processed (documents, files, images …)

External Storage Devices

• Used to store data until it is needed again.

• Disks (floppy,

harddrives), CD, DVD, Tape, Flash Memory.

Local Area Networks(LAN)

• Computers and resources connected together to share resources

• CWSS’s LAN --- 200 CPUs and servers, printers, ….

Wide Area NetworkWAN

• A network of computers and resources over a larger area.

• OCDSB …. 200 sites and connection to internet

Internet

• International Network• Shared resources

world wide• Files, e-mail, web

pages …• “Information

Highway”

World Wide Web(WWW)

• Browse web pages on servers located on internet

• EXPLORER, NETSCAPE, …. And FIREFOX (new)

5th Generation

• Still to come …• AI … artificial

intelligence• Voice recognition• ……