Transcript Unit I: Computer History and Basic Concepts

This lesson summarizes the historical
development of computing devices over
the past several hundred years.
Unit 1 Objectives
 I can use and understand basic computer terminology.
 I can outline historical developments in computer
technology and identify key figures in the history of
computers.
 I can analyze the impacts of technology on history and
society.
Did you know that the earliest
computers were not machines?
 Before the electronic computers of today, we relied
on individuals who used mathematics to solve
equations.
 At that time, computing was thought of as an
occupation.
 Since then, our understanding of computers has
changed and focused on machines.
 As computer technology has evolved,
computers have become an indisputable part of
our daily lives.
 This lesson introduces you to some of the first
forms of computers. It also explains the major
historical breakthroughs in computing
technology.
 By the end of the lesson, you will understand
how computing technology evolved into its
present form.
Early Computers
 The earliest computer devices were much
different than the ones we use today.
 They had no keyboard, mouse, or monitor.
They did not even use electricity.
 In fact, if you were to see one of these
devices today, you would probably not
realize you were looking at a computer.
Mechanical Computers
Because early computers did not
use electricity, they are referred to
as mechanical computers.
Mechanical computers rely on
parts that must be physically
moved in order to perform a task.
Mechanical Computers
 The earliest and simplest
mechanical computer is
known as the abacus.
 With these basic
machines, which are still in
use today, beads represent
numbers.
 People can solve addition
and subtraction problems
by sliding beads back and
forth on a string.
The zero position is for all beads to be
away from the central bar, as the beads on
the left are. The top two beads represent
five each, and the bottom beads represent
one. The units column has a single 'one'
bead and no 'five' beads, so this is one.
The tens column has one 'five' bead and
two 'one beads, representing 70. The
hundreds has a 'five' bead alone, so that is
500. Then there is 3000 and 60,000. So
the total number is 63,571.
Mechanical Computers
 The slide rule is another early computing device.
Developed in the 1600s, the slide rule is a mechanical
computer on a stick.
 It is commonly used to solve multiplication and division
problems. Because of its usefulness and convenient size,
most high school and college math students carried a slide
rule with them to class up through the mid 1970s.
 The slide rule was gradually replaced by handheld
calculators.
Mechanical Computers
 Several complex mechanical computers were also
developed in the 1600s.
 One of these was created by German scientist Wilhelm
Schickard. Schickard's computer used gears to add and
subtract numbers. It could also multiply and divide.
 About 20 years later, French mathematician Blaise
Pascal invented a similar device.
 However, communities in the 1600s were still largely
agrarian and had little use for mechanical computers.
As a result, complex mechanical computers were rare
and mostly used by scientists.
Computers in the Industrial Age
 European life began to change in the early 1800s.
 As industry spread across the continent, people started
leaving their farms to work in factories where goods
were produced.
 The more technologically advanced a factory was, the
more goods it could manufacture and sell for profit.
 Recognizing this trend, French inventor Joseph-Marie
Jacquard developed a system of punch cards to
increase productivity in textile factories.
Jacquard’s Loom
 When placed into a silk
loom, a type of clothmaking device, the punch
cards created a type of
primitive computer
program.
 The cards controlled the
patterns the loom followed,
which ultimately created
different types of cloths and
designs.
 Jacquard's invention greatly improved output and
reduced human error in the production process.
 The invention impressed French leaders, including
Napoleon.
 But a group of silk weavers feared the computing
device would put them out of work, so they destroyed
one of Jacquard's first looms.
 In the end, the invention was too useful to be ignored.
By the time of Jacquard's death in 1834, there were
more than 30,000 looms using punch cards.
The Analytical Engine
 In the 1830s, an English mathematician and scientist
named Charles Babbage built upon Jacquard's work.
 He invented the Analytical Engine, a machine that could
solve complex math problems using punch cards adapted
from Jacquard's silk loom.
 Unlike Jacquard's silk loom, which required workers to
manually insert a single punch card at a time, Babbage's
Analytical Engine used a series of punch cards. Once a
calculation had been completed, the punch card was fed
back into the machine where another punch card used the
calculation to complete a different problem.
 In this way, the Analytical Engine was the first machine to
utilize computer memory.
Heading Towards the 20th Century
 By the end of the 19th century, punch cards were being
utilized to increase efficiency across a variety of platforms.
 In 1890, Herman Hollerith's tabulating machine assisted
the United States with its 10-year census. The Tabulator
used punch cards to automatically count the number of
people in the country.
 Instead of taking eight years to compile, like the 1880
census, the 1890 census was completed in a single year.
 The success of the Tabulator led Hollerith to merge his
company with several others. They formed International
Business Machines (IBM) in 1924.
Answer each question before proceeding to the next slide.
1. How was data (information)
entered into Jacquard's silk
loom, Babbage's Analytical
Engine, and Hollerith's
Tabulator?
2. An abacus is primarily used for
______________ , while a slide
rule is primarily used for
_______________.
a. Addition and subtraction; multiplication and
division
b. Multiplication and division; addition and subtraction
c. Simple math; logarithms
d. Logarithms; simple math
3. What is the biggest
difference between the
computer you are using and
mechanical computers?
1. The information was entered using
punch cards.
2. A
3. Mechanical computers do not use
electricity. They have moving parts that
help perform tasks.
Early Electronic Computers
 Electricity began to change the lives of people
around the world in the early 20th century.
 Household appliances such as irons, toasters, and
lamps became electrically powered.
 In almost all cases, this use of electricity improved
the devices and made them more efficient.
 It was no surprise when computers began to utilize
this new power source as well.
Mark I
 One of the most notable early electronic computers was the
IBM Automatic Sequence Controlled Calculator (ASCC),
more commonly known as the Mark I.
 Completed in 1944 by Harvard professor Howard Aiken
with financial support from IBM, the Mark I used
electricity to open and close mechanical switches.
 When opened and closed, these switches created a type of
Morse code that the machine could understand.
 The Mark I was able to calculate problems with numbers
up to 23 digits long, a large calculation at the time.
Mark I
 Despite its unprecedented
computing power, the
Mark I's capabilities were
limited to arithmetic and
other math operations.
 Making matters worse, it
was about 50 feet long and
eight feet high and nearly
impossible to transport.
 Performing maintenance
on the computer's 750,000
parts and 500 miles of wire
was also challenging.
What is Binary Code?
 Binary code, the type of computer-based Morse code
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used by the Mark I, is still used in computers today.
Much like our alphabet conveys information to us
through letters, binary codes conveys information to a
computer.
In place of letters though, binary code uses just two
bits of data: electricity ON and electricity OFF.
To process information, the computer understands
each on and off switch as either a 0 or 1.
When eight of these bits of data are pieced together, a
computer byte is formed.
 Each computer byte has its own series of zeros and
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ones that forms a pattern the computer understands.
These patterns are then processed and turned into the
letters, punctuation marks, and numbers we recognize
on a computer monitor or other commands related to
computer functions.
When computer equipment has the acronyms MB
(megabyte) or GB (gigabyte) written on it, it is a
reference to binary code.
Megabyte means about 1 million bytes.
A gigabyte is roughly 1 billion bytes.
These acronyms are used to indicate the amount of
computer memory or a file's size.
ENIAC
 One of the most well-known early electronic computers was the
Electronic Numerical Integrator and Computer, or the ENIAC.
 It was proposed by John Von Mauchly and built by John Presper
Eckert, Jr. at the University of Pennsylvania.
 It was mainly used by the U.S. military and helped calculate,
among other things, the trajectory of artillery shells.
 Unlike the Mark I, which used mechanical
switches, ENIAC utilized vacuum tubes to
transmit signals and information. Similar in
appearance and size to light bulbs, vacuum
tubes had no moving parts. However, they
could still stop and start the flow of electricity
much like the switches in the Mark I.
a vacuum tube
 Completed in 1946, ENIAC
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has been called the first
successful
general purpose computer,
which means it could be
programmed to do multiple tasks.
It was able to perform 5,000 math
operations per second.
This type of performance meant
Employees monitor ENIAC
it was roughly 1,000 times faster
than the Mark I.
Like the Mark I, it was massive in size (about 100 feet
long and 10 feet tall).
It also contained tens of thousands of parts, including
18,000 vacuum tubes.
In total, the ENIAC cost about $500,000 to produce.
UNIVAC I
 By 1951, Eckert and Mauchly had left the University of
Pennsylvania and started their own company. They
began work on an upgrade to the ENIAC called the
UNIVAC I. This new machine was the first massproduced computer.
 Like the ENIAC, the UNIVAC I used vacuum tubes.
 It was sold to and used by a number of U.S.
government organizations, including the Census
Bureau, the air force, and the army.
 It was also used by many large commercial companies.
 The UNIVAC I is best known for helping CBS, a major
television network, accurately predict the results of the
1952 U.S. presidential election before the final results
were tallied.
 Afterward, other networks scrambled to acquire
computer technology to help assist them with
predicting election results.
 To this day television networks are able to project
winners in elections before the polls close because of
computers.
Development of the Transistor
 One of the major problems with the ENIAC, UNIVAC
I, and many other early electronic computers was their
heavy dependence on vacuum tubes.
 Although they were an improvement over mechanical
switches, vacuum tubes required a lot of energy and
produced a significant amount of heat. This often
required that they be placed in an air conditioned
room.
 The tubes were quick to wear down and in constant
need of replacement. With 18,000 tubes in the ENIAC
alone, maintenance became an ordeal.
 In 1947, three American physicists
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invented the transistor, a replacement
for the vacuum tube that took about a
decade to gain widespread use.
Although transistors performed the
same functions as vacuum tubes, they
used less energy, produced less heat,
and were more reliable. They also
worked faster, which allowed
Replica of the first transistor
computers to have more capabilities.
The transistor is considered one the greatest developments in
computer design and is widely regarded as one of the most
important inventions of the 20th century. In fact, they are still
included in most electronic devices built today.
The computers that are used today have millions, and sometimes
billions, of transistors within them. Trillions of transistors are
manufactured around the world every year.
Today’s transistors are thousands of times smaller than the original.
Answer each question before proceeding to the next slide.
1. What was the first successful
general computer?
A. Mark I
B. ENIAC
C. UNIVAC I
D. Tabulator I
2. How many bytes are in a
gigabyte?
A. 1
B. 1,000
C. 1 million
D. 1 billion
3. Why are transistors better
than vacuum tubes?
1. B. ENIAC
2. D. 1 billion
3. Transistors are faster, use less energy,
produce less heat, and are more reliable
than vacuum tubes.
Integrated Circuits
 Developed by American scientists in the 1960s,
integrated circuits allowed dozens of transistors to fit
into a single piece of silicon, a semiconductor that
allowed for easy data transfer.
 More commonly known as chips or microchips,
integrated circuits looked like
small electronic caterpillars.
 Large numbers of transistors
can be placed within a few
integrated circuits like those
pictured.
Microprocessors
 As scientists continued to develop integrated circuits, they
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found ways to fit even more transistors into smaller spaces.
Actually, the number of transistors within integrated
circuits has roughly doubled every two years since the
1960s.
Eventually this led to the development of microprocessors.
Microprocessors are integrated circuits that are capable of
processing all of the information for a computer.
This information ranges from individual applications, such
as Web browsers and games, to operating systems, a type of
software that tells the computer how to function. They also
process minor computer activities such as typing and
clicking the mouse.
Over the past few decades, microprocessors have become
faster and more powerful, helping computers to continually
expand their capabilities.
In 1969, the National Aeronautics and Space
Administration (NASA), the United States' space
exploration agency, launched Apollo 11, a mission that
landed humans on the moon for the first time. This
achievement would not have been possible without
computer technology. Did you know though that the
computer onboard that guided the Apollo 11 had less
computing power than many cell phones today?
What types of computing activities do you use your cell
phone for?
Personal Computers
 Apart from the abacus and slide rule, most
computers in the early 1970s were owned by
governments or other large institutions.
 Few individuals or small businesses could
afford computers at the time.
 That began to change in 1975 when the
Altair 8800 was released by Micro
Instrumentation Telemetry Systems.
Altair 8800
 The Altair 8800 is considered the world's first
personal computer because the average person could
afford and use it.
 It cost just $400 when it was released. However, it had
no keyboard or monitor, and it was difficult to use.
 Users had to create their own programs for the Altair
8800 using switches on the front cover. Red lights on
the front cover would then convey information back to
them.
 Despite its shortcomings, the Altair 8800's relatively
low cost allowed thousands of users to purchase the
device and experiment with improving its capabilities.
As a result, many individuals began careers in the
computing field.
 Two such individuals were Bill Gates and Paul Allen,
cofounders of the Microsoft Corporation, whose first
product was a programming language interpreter for
the Altair in 1975.
 About five years later, they began work on an operating
system for the IBM Personal Computer called MSDOS.
MS-DOS
 MS-DOS quickly became the industry
standard for personal computers.
 As computer technology improved, the
need for the MS-DOS operating system
increased with the demand for personal
computers.
 MS-DOS used a command-based interface which
required users to manually enter commands for a
program to run.
 However, many people found the command-based
operating system difficult to use.
Apple I
 One of Microsoft's main competitors over the years has
been Apple Computer, Inc. (now known as Apple Inc.).
 Established in 1976 by Steve Jobs and Stephen
Wozniak, the company's first product was called the
Apple I.
 The Apple I was an early
personal computer much
like the Altair 8800.
Graphical User Interfaces
 Over the years, Apple has released a series of
computers and operating systems known for their
easy-to-use GUIs.
 Microsoft Windows is an operating system that uses
Graphical User Interface (GUI).
 GUIs allow users to interact with their computers
using graphics, text, and icons displayed on a monitor.
 Since they are much easier to use than commandbased systems, GUIs gained widespread use.
Microsoft vs. Apple
 Microsoft's dominance continued into the 1990s with the
launches of Microsoft Windows and Office.
 Microsoft Office is a suite of products used for word
processing, spreadsheet creation, e-mail, and other
publishing functions.
 However, Apple has also expanded into other computerrelated products, including the popular iPod musical
device and the iPhone.
 Although the vast majority of personal computers in the
world use Microsoft Windows as their operating system,
the Apple operating system has seen its market share
increase in the 21st century.
Unit Review
 Computing power has increased dramatically from the
mechanical processes of the abacus and the punch
cards used by Jacquard to the microprocessors and
electronic computers of today.
 Computers have drastically shaped the way the world
works and how people interact – especially within the
past century and they continue to evolve.
 Everything from talking on our cell phones to landing
on the moon has been made possible because of this
technology.
 As you continue to learn about computers throughout
the rest of this course, take notice of the different types
of technology around you.
 Ask yourself, "How would my life be different without
cell phones, iPods, iPhones, smart phones, personal
computers, and smart boards?"
 Although you might take it for granted, much of the
computer technology that you enjoy today was either
not around or not affordable when your parents or
grandparents were your age.
Answer each question before proceeding to the next slide.
1. Which of the following is a
mechanical computer?
A. Abacus
B. UNIVAC I
C. ALTAIR 8800
D. ENIAC
2. Over the past several decades,
A. The number of punch cards within integrated
circuits has dramatically increased.
B. The number of punch cards within integrated
circuits has dramatically decreased.
C. The number of transistors within integrated
circuits has dramatically increased.
D. The number of transistors with integrated
circuits has dramatically decreased.
3. Why was computer use not
widespread before the
1970s?
1. A. abacus
2. C. The number of transistors within
integrated circuits has dramatically
increased
3. Prior to the 1970s, computers were bulky,
expensive and difficult to use. The
average person did not have the means or
the knowledge to use them.
Congratulations!
 This concludes the Instruction Module for Unit I.
 Make sure your Study Guide and notes are complete.
 Turn your completed Study Guide in to Ms. Moran for
feedback.
 Request or print out the Homework assignment and
complete it to practice for the test.
 You should be prepared to complete the unit
assessment no later than Friday afternoon.