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The Digital Deluge

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Title: The Digital Deluge


1
The Digital Deluge
  • Learning in Retirement
  • David Coll
  • Professor Emeritus
  • Department of Systems and Computer Engineering
  • Winter 2009

2
(No Transcript)
3
Welcome to The Digital Deluge
  • My name is David Coll and
  • In the next few weeks Im going to try and give
    you a feel for whats going on in a world awash
    in digital information.
  • Well look at
  • the jargon,
  • the sources,
  • the volumes,
  • the technology,
  • the societal impact, and
  • how some are coping.

4
  • This is a lecture series about the flood of
    information created by new technologies.
  • The problem in offering a course about this
    subject is that there is way too much information
    to handle.
  • But we have ways of coping
  • For example
  • Clear and simple instructions

5
(No Transcript)
6
First - My Co-ordinates
  • Professor Emeritus
  • in the Department of Systems and Computer
    Engineering, Carleton University
  • dccinfo_at_sympatico.ca
  • http//www.sce.carleton.ca/faculty/coll.htm
  • 613-225-4229

7
Information
  • The world is awash in INFORMATION.
  • Our senses sight, hearing, smell, touch, and
    taste are bombarded with inputs from all sides
  • Information is essential for our survival.
  • But
  • Lets narrow it down somewhat

8
  • We might limited ourselves to information that
    comes to us through a medium mediated
    communications
  • Print
  • newspapers, magazines, books, flyers
  • Posters
  • Radio
  • Television
  • Recordings music, images, videos
  • The Telephone

9
  • As well as through
  • the Internet and
  • the World Wide Web
  • We will exclude information communicated to us
    through spectral channels by mediums wearing
    star-studded gowns and too many bracelets

10
Introduction
  • The rapid growth and deployment of digital
    information processing and communications
    technology is changing our world, the way we do
    business, and the way we live.
  • Information be it text, data, images, music,
    speech, or television is acquired, stored,
    processed, communicated, received, and presented
    in digital form, i.e., as numbers.

11
  • The resulting torrent of information is so vast
    that some have dubbed it the The Digital
    Deluge.
  • deluge
  • 1
  • a an overflowing of the land by water
  • b a drenching rain
  • 2 an overwhelming amount or number, as
    inreceived a deluge of offers

12
The Deluge from Various Perspectives
The extent, rapidity of acceptance, and
pervasiveness of digital technology is almost (?)
beyond comprehension.
13
The Digital Deluge
  • Data is omnipresent. Everywhere we go, we
    encounter it, in our business transactions,
    subscription lists, email, etc.
  • To put the growth of data in perspective, every
    18 months the processing capacity of the world
    doubles, but at the same time data has been
    doubling every nine months.
  • http//itmanagement.earthweb.com/datbus/article.ph
    p/1495861

14
The Digital Deluge
  • One of the scariest statistics in recent memory
    is IDCs prediction that the amount of digital
    data between now and 2010, reaching a whopping
    988 billion gigabytes.
  • (Thats a figure so huge, it would be helpful
    to have one of those goofy yet helpful references
    to put it into context. How many football fields
    it would fill, for example.)
  • http//www.itbusinessedge.com/blogs/tve/?p98

15
ScienceDaily (Nov. 8, 2007)
  • Most people have a few gigabytes of files on
    their PC.
  • In the next decade, astronomers expect to be
    processing 10 million gigabytes of data every
    hour from the Square Kilometre Array telescope.
  • http//www/sciencedaily.com/releases/2007/11/07110
    7091524.htm

16
  • When the Large Hadron Collider at CERN starts
    running in 2008, it will be the biggest
    scientific instrument in the world.
  • Thousands of scientists across the planet will be
    clamouring for access to the streams of data that
    will come out of the instrument.
  • The LHC will produce about 15 Petabytes of data
    every year, which is more than 1000 times the
    amount of information in book form printed every
    year around the world.
  • If written to CDs, the stack of CDs would be
    about 20 km in height!
  • http//gridcafe.web.cern.ch/gridcafe/GridatCERN/gr
    idatcern.html

17
From IDC Report
  • With a compound annual growth rate of almost
    60, the digital universe is growing faster and
    is projected to be nearly 1.8
    zettabytes (1,800 exabytes) in 2011, a 10-fold
    increase over the next five years
  • At 281 billion gigabytes (281 exabytes), the
    digital universe in 2007 was 10 bigger than
    originally estimated

18
  • IDCs new research shows the digital universe is
    growing more rapidly than original estimates as a
    result of accelerated growth in worldwide
    shipments of
  • digital cameras,
  • digital surveillance cameras, and
  • digital televisions
  • as well as
  • a better understanding of information replication
    trends.
  • They didnt mention traffic to and from cell
    phones , iPhones, Blackberries and the ilk..

19
  • The digital universe in 2007 was equal to almost
    45 gigabytes (GB) of digital information for
    every person on earth or the equivalent of over
    17 billion 8 GB iPhones.
  • Other fast-growing corners of the digital
    universe include those related to
  • Internet access in emerging countries
  • sensor-based applications
  • data centers supporting cloud computing
  • social networks comprised of digital content
    created by many millions of online users.

20
The Digital Deluge
  • Whats it all about and what can we do about it?
  • Maybe we can not only survive the Digital Deluge,
    but use it to our advantage.
  • Hey! Didnt Noahs kids learn to water ski behind
    the Arc?

21
Lets Start with Five Questions
  • Where does information come from?
  • How does it get to be digital?
  • How does it get to us?
  • Why is it a problem?
  • What is being done to cope with it?

22
Where Does the Information Come From?
23
Information Generators
  • Arts
  • Literature
  • History
  • Language
  • Education
  • Religion
  • Science and Technology
  • Government/Bureaucracy
  • Commerce

24
  • Administration
  • Medicine and Pharmacology
  • Geography and Cartography
  • Entertainment
  • News

25
Traditional Sources
  • Media
  • Print Books, Newspapers
  • Film
  • Radio and TV Broadcast
  • Accumulated Knowledge
  • Libraries
  • Repositories
  • Folk Lore

26
  • Publications
  • Books, Newspapers, Magazines, Professional
    Journals
  • Radio and TV
  • Personal Communications and Correspondence
  • Sensors and Instrumentation
  • .

27
  • Libraries and Repositories
  • Publications, Reference Material, Dictionaries,
    Encyclopedia, Catalogs
  • Personal Creation
  • Records
  • Bills, Accounts, Investments, Wills, Warranties,
    Contracts,
  • Libraries
  • Books, Magazines, Clippings,
  • Diaries and Writings
  • Recordings
  • Audio, Photo, Film, Video
  • Computer Files

28
How Does It Get To Us?
  • Purchase and Own
  • Delivery Services
  • Mail, Newspapers, Magazines
  • Broadcast Services
  • Radio
  • Television
  • Message Services
  • Telegraph
  • Teletype
  • Data Communications
  • File Transfers, Data Collection
  • Transactions

29
Where did this Deluge come from?
  • The major reason the world is awash in
    information in digital form is the
  • COMPUTER
  • Actually the ability to represent and process
    information on digital form
  • But, that is only half the story.

30
  • An isolated computer is just a fancy adding
    machine or typewriter with memory
  • So, the deluge results from the fact that all the
    worlds computers are connected!
  • Well, most all.
  • The ability to communicate information is an
    essential factor behind the deluge, and
  • Communications is done digitally..

31
Whats the Problem?
  • There is so much information/data.
  • Entertainment, medical, scientific research,
    educational, literature, news, personal
  • We are not always sure about just what
    information there is in the data
  • information often implies knowledge whereas
    we are talking about the volumes of data that are
    generated whether they make sense or not.

32
The Culprit?
  • A mixture of
  • The Internet
  • networked computers, ubiquitous communications,
  • Applications
  • the WWW, information processing
  • and Smart Machines
  • Enabled by the evolution of common digital
    technologies throughout.

33
So Whats New?
  • A common technological basis for the
  • acquisition,
  • distribution and
  • handling
  • of information in digital formats.
  • A basis that has very recently reached levels of
    maturity that have unleashed information in a
    flood of incomprehensible immensity.

34
  • Thats the Punch Line
  • But Why The Deluge Now?
  • Because we can!

35
Enabling Technologies
36
  • But, first
  • Let us pause for a short break .

37
What will we do?
  • Well look at sources of the information
    explosion in areas that affect us
  • Mobile telephones
  • Digital cameras
  • Music iPods, CDs, DVDs
  • HDTV
  • The Internet and Web Applications
  • Libraries and other repositories
  • Smart terminals
  • Home automation
  • Scientific Research, and so on.

38
  • We will look at what digital means
  • How the adoption of digital technology is used to
    create information, store and process it,
    communicate and display it.
  • Why we are deluged with digital information,
    i.e.,
  • Whats behind the sudden onslaught of
    information, where this surge is coming from, how
    its to be handled, and what the future holds.

39
  • Then, hopefully we can discuss some ways of
    coping, and even enjoying the deluge
  • Lets start with some definitions

40
Terminology
  • Misuse of terminology can lead to lead to
    misunderstanding.
  • Being precise in one's terminology can be
    important.
  • It is also important to understand the historical
    origin of terms, to better understand their
    meaning, and to realize how different points of
    view can modify meaning.

41
Scale and Scope of the Deluge
  • How deep is the flood?
  • If we are in water that is 6 feet deep we have a
    feel for what sort of situation we are facing
  • But, whats an exafoot?
  • What are these funny names for data rates and
    volumes?

42
  • The basic digital (binary) unit is the bit, a
    single binary digit with values 0 or 1.
  • In Digital Communications, one usually refers to
    data rates in terms of bits per second, or bps.
  • Data rates, often mistakenly termed bandwidth,
    are expressed as the number of bits transmitted
    per second
  • as in 56 kbits per second (kbps) or 1.544
    megabits per sec (mbps)

43
Common Data Rates
  • Data Rate speeds derive from teletype and
    telephone services
  • Originally, everything was a multiple of the
    telegraph speed of 75 bits per second
  • 300, 1200, 2400, 4800, 9600 bps
  • Then multiples of the basic telephone sampling
    speed of 64,000 kbps took over, giving services
    at the T1 TDM carrier speed of 1.544 Mbps, and
    multiples of it.

44
Common Optical FibreTransmission Rates in
Megabytes per second.
Optical Line Rates
OC-1 51.84
OC-3 155.52
OC-12 622.08
OC-48 2,488.32
OC-192 9,953.28
OC-768 39,813.12
45
Optical Fibre Transmission Rates - in Megabytes
per second- MBps
  • The OC192 rate is 9,953.28 megabits per second,
    or almost 10,000 Mbps 10 gigabits per second.
  • This number is 192 times 51.84 mbps
  • 51.84 810 x 8,000 x 8, or 810 x 64,000
  • The number of bits per second in a basic SONET
    frame used for the transmission of 810 voice
    channels.

46
Prefix Symbol Base 10 Base 2
yotta Y 24 80
zetta Z 21 70
exa E 18 60
peta P 15 50
tera T 12 40
giga G 09 30
mega M 06 20
kilo k 03 10
hecto h 02 -
deka da 01 -
deci d -01 -
centi c -02 -
milli m -03 -
micro m -06 -
nano n -09 -
pico p -12 -
femto f -15 -
atto -18 -
zepto z -21 -
yocto y -24 -
In communications, electronics, and physics,
multipliers are defined in powers of 10 from
10-24 to 1024, proceeding in increments of three
orders of magnitude (103 or 1,000). In IT and
data storage, multipliers are defined in powers
of 2 from 210 to 280, proceeding in increments of
ten orders of magnitude (210 or 1,024).
47
But, how many is that in base 10?
  • Kilo 1 thousand 103
  • Mega 1 million 106
  • Giga 1 billion 109
  • Tera 1 trillion 1012
  • Exa 1 quadrillion 1015
  • Peta 1 quintillion 1018
  • Zetta 1 sextillion 1021
  • By the US short scale check
    http//en.wikipedia.org/wiki/Names_of_large_number
    s

48
Computer Memory and Processing
  • In digital computers, the basic element of
    information storage is the byte, an 8-bit binary
    number.
  • The basic storage element is a word, and is
    usually 8, 16, 32 or 64 bits long, or 1, 2, 4, or
    8 bytes.
  • It is common to measure the size of a computer
    memory in terms of powers of 2,
  • e.g.
  • 1 Kilobyte 210 1024 bytes.

49
Counting Bytes
  • Kilobyte 1 KB 210 1024 bits 1 x 103
  • Megabyte 1MB 220 bits, or 1,048,576 bits
    1 x 106
  • Gigabyte 1GB 230 bits 1,073,741,824 bits
  • Terabyte 1TB 240 bits 1,099,511,627,776 bits
  • Exabyte 1 EB 250 bits 1,125,899,906,842,624
    bits 1 x 1015
  • Petabyte 1 PB 260 bits 1,152,921,504,606,846,
    976 bits 1 x 1018

50
Bits and Bytes
  • Transmission speeds invariably refer to bits per
    second
  • e.g. 1.544 Mbps
  • File sizes refer to bytes
  • e.g. 1 Megabyte of RAM 1024 Kilobytes or
    1,048,576 bits but communications rarely, if
    ever, refers to bits at all.

51
The Digital Thing Whats the Big Idea, Anyway?
  • Digital is a word (mis)used to describe
    information (often called data) in discrete form,
    and the subsequent processing of that
    information,
  • as opposed to information that occurs in a
    continuous, or analog form.

52
  • Digital means discrete (like whole numbers) and
    Analog means continuous (like physical properties
    such as temperature, volume, etc.).
  • The term analog comes from early computers (circa
    WWII) used to solve differential equations with
    continuous variables,
  • as contrasted with discrete state machines (like
    an elevator controller) built from open-or-closed
    switches or on-off digital circuits

53
Definitions (from whatis.com)
  • Analog
  • Using physical representation
  • Relating to a system, device that represents data
    variation by a measurable physical quality such
    as temperature, volume, distance, weight,
    pressure
  • Which is continuous in time or space and value

54
Definitions
  • Digital
  • Representing data as numbers
  • Processing
  • Operating on
  • Storing
  • Transmitting
  • Displaying
  • Data in the form of numerical digits, as in a
    digital computer

55
  • Representing a physical quantity
  • such as sound, light, or electricity
  • by means of samples
  • taken at discrete times (or places)
  • and given numerical values
  • usually in the binary system
  • as in a digital audio recording
  • or in digital television
  • or in digital photography

56
In Communications
  • Analog is used to refer to systems with signals
    that are continuous in value and time
  • such as AM and FM, where the electrical signals
    are representations of the information signals.

57
Amplitude Modulation (AM)
ANALOG
58
Phase or Frequency Modulation (FM)
59
In Communications
  • Digital is used to refer to discrete-state,
    discrete-time signals that can take on only
    specific values at specific times
  • such as
  • sampled/quantized signals,
  • pulse modulated signals,
  • and to data communication signals in general.

60
Digital Modulation Discrete in Time and Value
61
Parameters of Information Sources Systems
  • Analog (continuous functions of time, space,
    weight, )
  • voice, audio, image, video, temperature
  • Bandwidth frequency (harmonics) range
  • Statistics amplitude distribution, power,
    spectrum (frequency content, harmonics)
  • Digital (sets of numbers)
  • ASCII characters, computer words,
  • Bit Rate bps, kbps, Mbps, Gbps, Tbps, Ebps,

62
How does Information Become Digital?
63
Digital Representation
  • Information that is naturally discrete, such as
    state of a light switch (on-off), integers, or
    text can be represented by binary numbers in
    obvious ways.
  • Text (as generated on a keyboard) is often
    represented by 8-bit binary numbers.
  • Speech may be represented by a pressure wave,
    which is continuous in time and value and has
    to be sampled and quantized to be represented
    digitally.

64
Discrete Information
  • Some information, such as numerals and characters
    is discrete and can be represented digitally
    easily
  • Take characters of the English Language for
    example
  • The American Standard Code for Information
    Interchange (ASCII) is the binary representation
    used in teletype messaging and adopted as a
    universal computer character representation.

65
(No Transcript)
66
Serendipity
  • Early minicomputers such as Digital Equipment
    Corporation (DEC) PDP machines used
    teletypewriters as terminals
  • They had
  • keyboards that generated ASCII code words
  • printers that accepted ASCIII code words and
  • punched paper tape I/O that could be used to save
    and replay messages.

67
  • The ASCII code set including
  • text formatting
  • CR and LF
  • and message formatting
  • SOH, STX ETX, EOT
  • Became the way computer communications over
    leased and dial-up telephone lines started
  • Except for a bunch of computer geeks who used Sun
    Microsystems workstations which had a different
    communications scheme built-in.

68
Common Sense Digitization of Analog Information
  • All continuous signals can be represented by a
    collection of numbers to any degree of accuracy
    by
  • sampling often enough and
  • using enough quantization levels to represent
    the signal value at the sampling instants.
  • determined by the number of digits in the
    representation

69
Analog-to-Digital Conversion
  • Two stage process
  • Sample
  • Sampling Theorem
  • Nyquist Rate
  • Quantize
  • Precision, SNR ( average error)
  • Note a digital representation of an analog value
    always has error

70
The Sampling Theorem
  • Shannons Sampling Theorem states that
  • any bandlimited signal may be represented by
    samples taken at a rate of twice its highest
    frequency, and
  • may be reconstructed without error if the
    appropriate interpolation functions are used.
  • Twice the highest frequency is called the
    Nyquist Rate.
  • Physically unrealizable sinx/x or (sinc)
    functions.

Nerd Alert
71
Impulse Sampling
72
Reconstruction
73
Summary
  • All signals can be represented by a collection of
    numbers to any degree of accuracy by sampling
    often enough and using enough quantization levels
    to represent the signal value at the sampling
    instant.

74
Summary (for irrepressible nerds only)
  • Shannons Sampling Theorem states that any
    strictly bandlimited function may be presented by
    sampling at a rate that is at least twice as fast
    as the highest frequency in the signal, and that
    it may be recovered without distortion by passing
    the (impulse) samples through an ideal low-pass
    filter with a bandwidth equal to that of the
    signal.

75
Quantization
  • For processing, storage or communication, samples
    with infinite precision must be quantized
  • Such that a range, or interval, of values is
    represented by a single, finite precision, number
  • For example, by a finite binary number.

76
Quantization
7
7
7
7
7
6
5
5
4
3
3
2
2
1
1
1
time
-2
-2
-3
-3
-3
-4
77
Reconstitution
7
7
7
7
7
6
5
5
4
3
3
2
2
1
1
1
time
-2
-2
-3
-3
-3
-4
-2
Quantum Boundary
Actual Value
ERROR
-3
Reconstruction Value
-3
Quantum Boundary
-4
78
Quantization Error (for nerds and audiophiles)
  • The quantization error depends on the number of
    distinct quantization intervals used.
  • If N binary digits are used, the number of
    distinct intervals is 2N.
  • The signal-to-quantization-error ratio is about
    (6N 1.8) dB.

79
Binary Representation
  • Once information is discretized, or sampled, a
    number can be assigned to represent the value of
    each sample.
  • The number can be expressed as a binary number,
    e.g., 2009 is
  • 1024 512 256 128 64 32 8 4 1
  • 1x 210 1x 29 1x 28 1x 27 1x 26 1x 25 1x
    23 1x 22 1x 20
  • 11111101101

80
  • Summary
  • The basis of the Digital Deluge is the universal
    adoption of a technology that can create,
    process, and communicate information that is
    represented in digital form.

81
  • So much for Digital Representation
  • Now, lets look at Digital Information
    Technologies
  • But, first
  • Let us pause for a short break .

82
Let us look at the Digital Technologies
  • Communications
  • Computing

83
Digital Communications
  • We have
  • Sources of Information
  • That create information
  • Destinations for Information
  • That use information
  • and we have
  • Communications Networks
  • That provide connectivity between them
  • We also have Terminals
  • That interface (connect) the Sources and
    Destinations to the Networks.

84
A Taxonomy of Telecommunications
  • Sources
  • Channels
  • Destinations

Dest
Term
Channels
Source
Term
Term
Dest
85
What are Digital Communications?
  • Modern Telecommunication Systems are designed to
    accept and deliver information made up of
    sequences of binary signals.
  • These systems and the connections through them
    are enabled and controlled by computers.

86
What is Special About NOW? Why the Deluge NOW?
  • Realization of the Telecomm Dream
  • Unified Communications
  • ubiquitous high speed, multimedia, reliable,
    standardized networks
  • The All-IP Multimedia Network
  • The Internet and the WWW
  • Ubiquitous Broadband Access
  • Wired (FTTP)
  • Wireless(Cellular/WLAN)

87
More on Communications
  • We will discuss communications later when we look
    at delivering digital information.

88
Computers Universal Digital Processing Machines
  • Computers are universal digital machines that can
  • accept information in digital form
  • store it
  • process it in many ways
  • output it to various devices
  • display it
  • communicate it
  • All under control of a set of pre-determined
    steps called a program.

89
The Evolution of the Computer
  • Intelligent Information Agents
  • Communications, Processing, Control
  • Programmable
  • Powerful Hardware speed, memory
  • Handheld/Mobile
  • Robotic
  • autonomous tasks
  • in touch with local environment

90
Terminals and Switches
  • Terminal Equipment
  • the sources and destinations of information, are
    digital machines, i.e., computers, in the
    broadest sense.
  • Network Switches are also computers.

91
  • Software Development
  • Highly evolutionary
  • Use of complex components
  • Standardization

92
Intelligent Agent Telematics
93
What are Computers Anyway?
  • Computers are digital machines that can acquire
    or create, store/retrieve, process, display, and
    communicate information in the form of finite
    binary numbers.
  • A computer is an electronic machine composed of
    three parts
  • Input/Output
  • Memory
  • Central Processor Unit

94
CENTRAL PROCESSING UNIT C PU
MEMORY
BUS
95
  • Data in the form of binary words
  • Can be moved
  • From the input unit
  • to the memory or
  • to the processor
  • From the memory
  • to the processor or
  • to the output unit

96
Components
  • The Memory consists of a number of storage
    spaces,
  • each having a unique address,
  • in which data in the form of finite-length binary
    numbers can be stored
  • Instructions, in the form of binary numbers, are
    also stored in the memory

97
Instructions the Basic Operation
  • What the computer does is specified by
    INSTRUCTIONS
  • An Instruction specifies
  • what operation is to be performed on
  • what data, and
  • where to put the result
  • Instructions are coded as binary words and stored
    in the same memory as the data

98
(No Transcript)
99
Memory
Address Content
0000 10100111
0001 01101000
0010 11001001
0011 11111111
0100
0101
0110
0111
1000
1001
---
1111
100
  • The Central Processor Unit (CPU) consists of
  • a Program Counter, which holds the address of the
    instruction being executed.
  • an Instruction Register, which holds the
    instruction being executed
  • An Address Register, which holds the address of
    the operand
  • An Arithmetic Logic Unit, which carries out the
    current instruction i.e. the instruction being
    executed

101
CPU
102
Instructions
  • There are instructions to
  • Move data
  • Perform arithmetic or logical operations on data,
    including comparisons
  • Change the order in which instructions are
    carried out
  • Control the machine and its peripherals

103
  • The instructions stored in memory constitute a
    program.
  • A single address computer instruction usually has
    two parts
  • The Operation Code and the Operand
  • e.g., ADD B
  • which, when executed
  • leaves the sum of the contents of the Accumulator
    and the contents of Memory Location B in the
    Accumulator  
  •  

104
Instruction Format
OP CODE
OPERAND ADDRESS
105
  • When an instruction is executed
  • It is moved
  • from the location indicated by the Program
    Counter
  • into the Instruction Register
  • The Program Counter is incremented by one
  • The operation and operand are ascertained
  • and the operation is carried out.

106
Instruction Cycle
  • FETCH
  • Get the contents of the Memory Location whose
    address is in the Program Counter.
  • Put the contents of the Operation Code Field in
    the Instruction Register.
  • Put the contents of the Address Field in the
    Address Register
  • Increment the Program Counter.
  • EXECUTE
  • Carry out the instruction in the Instruction
    Register on the data referred to by the contents
    of the Address Register

107
Addition
1 01100001
01100001
LDA A
11100101
11100101
A
01111011
01111011
B
ADD B
C
STA C
108
THEN WHAT DOES THE COMPUTER DO?
109
  • What is the most important instruction?
  • Answer HALT.

110
Input-Output Units
  • Input Units keyboard, scanner, modem, external
    disk memory, analog-to-digital converter, camera,
    sensor.
  • Output Units screen, printer, modem, external
    memory digital-to-analog converter, controller.

111
  • OK, so that sort of explains how a digital
    computer works
  • In a nutshell
  • the set of operations required to solve the
    problem at hand
  • add up the bills, or print the characters in a
    book, or whatever,
  • are expressed in a program (a list of
    instructions that when executed achieve the
    desired result) and the program is run, i.e.,
    the individual instructions are carried out one
    after another
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