CS101: Intro to Computing

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CS101 Introduction to Computing
Lecture 2
Evolution of Computing
During the Last Lecture …
• We learnt about the Analytical Engine - the first
general-purpose, digital computer – and its inventor
Charles Babbage
• We had a discussion about the key strengths (speed,
do not get bored) and weaknesses (pattern
recognition, innovative ideas) of the modern computer
Today’s Goal
To learn about the evolution of computing
To recount the important milestones and the key
events
To learn about the steps that took us from
Babbage’s idea of the Analytical Engine to
today’s ultra-smart hand held computers
But first, why should we spend time
on recounting the events of the past
Why not just talk about what is
happening in computing now and
what is going to happen in the future?
Why?
• If you do not learn from the history,
your condemned to repeat it
• Recounting the events of the past
provides an excellent opportunity to:
– learn lessons
– discover patterns of evolution, and
– use them in the future
• If we learn from history well, we will:
– neither repeat the mistakes of the past
– nor would we waste time re-inventing
what already has been invented
Babbage’s Analytical Engine - 1833
• Mechanical, digital, general-purpose
• Was crank-driven
• Could store instructions
• Could perform mathematical calculations
• Could store information permanently in punched cards
Click here to see the picture of
punched card
Punched Cards - 1801
• Initially had no relationship with computers
• Invented by a Frenchman named Joseph-Marie
Jacquard for storing weaving patterns for automated
textile looms (“khuddian”)
• Their value for storing computer-related information
was later realized by the early computer builders
• Punched cards were replaced my magnetic storage
only in the early 1950s
Protests Against Jacquard’s Invention
• Hand weavers saw the automatic loom as a
threat to their livelihood
• They burned several of the new machines
• A few weavers even physically assaulted
Jacquard
Turing Machine - 1936
• Alan Turing of Cambridge University presented his
idea of a theoretically simplified but fully capable
computer, now known as the “Turing Machine”
• The concept of this machine, which could theoretically
perform any mathematical computation, was very
important in the future development of the computer
• You will learn about the details of the “Turing Machine”
in your advanced Computer Science courses
Another contribution by Alan Turing
• The “Turing test”
• A test proposed to determine if a computer has
the ability to think
• So far no one has built a computer that can
pass that test – there is cash prize of
US$100,000
Terminal
Human
Terminal
Interrogator
Machine
on its own
Turing Test
• An interrogator is connected to one person and
one machine via a terminal, therefore can't see
her counterparts
• The interrogator’s task is to find out which of
the two candidates is the machine, and which is
the human only by asking them questions. If the
machine can "fool" the interrogator, it passes
the “Turing Test”.
Vacuum Tube - 1904
• John Fleming, an English Physicist, developed the
very first one
• These electronic devices consist of 2 or more
electrodes encased in a glass or metal tube
• They along with electric relays were used in the
construction of earlier computers
• These tubes have now been almost completely
replaced by more reliable and less costly transistors
ABC - 1939
• Attanasoff-Berry Computer
• John Attanasoff & Clifford Berry at Iowa State College
• World’s first electronic computer
• The first computer that used binary numbers instead
of decimal
• Helped grad students in solving simultaneous linear
equations
Harvard Mark 1 - 1943
• Howard Aiken of Harvard University
• The first program controlled machine
• Included all the ideas proposed by Babbage for the
Analytical Engine
• The last famous electromechanical computer
ENIAC – 1946
• Electronic Numerical Integrator And Computer
• World’s first large-scale, general-purpose
electronic computer
• Built by John Mauchly & John Echert at the
University of Pennsylvania
• Developed for military applications
• 5,000 operations/sec, 19000 tubes, 30 ton
• 9’ x 80’
• 150 kilowatts: Used to dim the lights in the City
of Philadelphia down when it ran
Transistor - 1947
• Invented by Shockly, Bardeen, and Brattain at
the Bell Labs in the US
• Compared to vacuum tubes, it offered:
–
–
–
–
much smaller size
better reliability
much lower power consumption
much lower cost
• All modern computers are made of
miniaturized transistors
• Tubes replaced mechanicals
• Transistors replaced tubes
• What is going to replace the transistors?
EDVAC – 1948
• Electronic Discrete Variable Automatic Computer
• Built by Echert & Mauchly and included many design
ideas proposed by Von Neumann
• The first electronic computer design to incorporate a
program stored entirely within its memory
• First computer to use Magnetic Tape for storing
programs. Before this, computers needed to be rewired each time a new program was to be run
Floppy Disk - 1950
Invented at the Imperial University in Tokyo by
Yoshiro Nakamats
Provided faster access to programs and data
as compared with magnetic tape
Compiler - 1951
• Grace Hopper of US Navy develops the very
first high-level language compiler
• Before the invention of this compiler, developing
a computer program was tedious and prone to
errors
• A compiler translates a high-level language
(that is easy to understand for humans) into a
language that the computer can understand
UNIVAC 1 - 1951
•
•
•
•
•
•
•
•
UNIVersal Automatic Computer
Echert & Mauchly Computer Company
First computer designed for commercial apps
First computer that could not only manipulate
numbers but text data as well
Max speed: 1905 operations/sec
Cost: US$1,000,000
5000 tubes. 943 cu ft. 8 tons. 100 kilowatts
Between 1951-57, 48 were sold
BASIC - 1965
• Beginner All-purpose Symbolic Instruction Code
• Developed by Thomas Kurtz & John Kemeny at
Dartmouth College
• The first programming language designed for the nontechies
• The grand-mother of the most popular programming
language in the world today – Visual BASIC
Computer Mouse - 1965
• Invented by Douglas Englebart
• Did not become popular until 1983, when
Apple Computers adopted the concept
ARPANET - 1969
• A network of networks
• The grand-daddy of the today’s global Internet
• A network of around 60,000 computers
developed by the US Dept of Defense to
facilitate communications between research
organizations and universities
Intel 4004 - 1971
• The first microprocessor
• Microprocessor: A complete computer
on a chip
• Speed: 750 kHz
Altair 8800 - 1975
• The commercially available 1st PC
• Based on the Intel 8080
• Cost $397
• Had 256 bytes of memory; my PC at home
has a million times more RAM (Random
Access Memory)
Cray 1 - 1976
• The first commercial supercomputer
• Supercomputers are state-of-the-art machines
designed to perform calculations as fast as the current
technology allows
• Used to solve extremely complex tasks: weather
prediction, simulation of atomic explosions; aircraft
design; movie animation
• Cray 1 could do 167 million calculations a send; the
current state-of the-art machines can do many trillion
(1012) calculations per second
IBM PC & MS DOS - 1981
• IBM PC: The tremendously popular PC;
the grand-daddy of 95% of the PC’s in
use today
• MS DOS: The tremendously popular
operating system that came bundled
with the IBM PC
TCP/IP Protocol - 1982
• Transmission Control Protocol/Internet Protocol
• The communications protocol used by the
computer networks, including the Internet
• A communication protocol is a set of rules that
governs the flow of information over a network
Apple Macintosh - 1984
• The first popular, user-friendly, WIMPbased PC
• Based on the WIMP (Windows, Icons,
Menus, Pointing Device) ideas first
developed for the Star computer at
Xerox PARC (1981)
World Wide Web -1989
• Tim Berners Lee – British physicist
• 1989 – At the European Center for Nuclear
Energy Research (CERN) in Geneva
• 1993 - The 1st major browser “Mosaic” was
developed at the National Center for
Supercomputing Applications at the University
of Illinois, Urbana-Champaign
Deep Blue -vs- Kasparov - 1997
It could analyze up to 300 billion
chess moves in three minutes
In 1997 Deep Blue, a supercomputer
designed by IBM, beat Gary Kasparov, the
World Chess Champion
That computer was exceptionally fast, did
not get tired or bored. It just kept on
analyzing the situation and kept on
searching until it found the perfect move
from its list of possible moves
Mobile Phone-Computer
• A small computer, no bigger than the hand set
of desktop phone
• Can do whatever an Internet-capable computer
can plus can function as a regular phone
• First consumer device formed by the fusion of
computing and wireless telecommunication
What is he next major Milestone?
1. Mechanical computing
2. Electro-mechanical computing
3. Vacuum tube computing
4. Transistor computing
(the current state-of the-art)
5. Quantum computing
Quantum
Mechanics
QUANTUM MECHANICS is the
branch of physics which
describes the activity of
subatomic particles, i.e. the
particles that make up atoms
What is he next major Milestone?
• Quantum computers may one day be millions of times
more efficient than the current state-of-the-art
computers.
• They take advantage of the laws that govern the
behavior of subatomic particles.
• These laws allow quantum computers to examine all
possible answers to a question simultaneously
• For example, if you want to find the largest from a list
of four numbers:
– The current computers require on average 2 to 3 steps to
get to the answer
– Whereas, the quantum computer may be able to do that in a
single step
For further info …
Read the following article that is available on the Web:
Quantum Computing with Molecules
by Neil Gershenfeld and Isaac L. Chuang
http://www.sciam.com/1998/0698issue/0698gershenfeld.html
What have we learnt today?
Focus of the Next Lecture
The World Wide Web
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