Ujung Gelas

BAHASA INGGRIS II
(ENGLISH FOR COMPUTER)
Meeting 1
What is a computer?
Computer is a machine that can accept
data and process it according to a stored
program of instructions and then give the
result via output devices. An electronic
symbol-manipulating system that’s
designed and organized to automatically
accept and store input data, process them,
and produce output results under the
direction of detailed step-by-step stored
program of instructions.
How a computer works can be explained
with this simple block diagram:
Input
5+4
Process
Output
9
Storage
For example you input any data using
input devices, 5 + 4. Then this data will be
processed in a computer. This process will
be held by a device called processor. After
the process is completed, the result will be
held by an output device. Sometimes, the
computer needs to save the process for a
particular need. For example for further
use in the future. In this case the computer
will save the process to a device called
storage. That’s the way computer works.
Task 1
Find the synonym from the passage (Slide 2 - 4)
which mean the same as:
1. Keep/save : _________________
2. Through : _________________
3. Commands : _________________
4. Made : _________________
5. Arranged : _________________
6. Instruments : _________________
7. Very definite : _________________
8. As stated by : _________________
9. Finished : _________________
10. Necessity : _________________
Now have a look at all devices in that
process. First one is input device. There
are many kinds of input devices. The most
commonly used is keyboard. Others are
mouse, light pen, microphone, track ball,
camera (for example webcam), etc. We
can say that input device is any kinds of
devices that can be used to input any data
to a computer.
The second device is the processor.
This is the brain of the computer which
holds all data processing in a computer.
The processor is created based on
semiconductor material like Germanium
(Ge) and Silicon (Si). The form of
processor was not like the form we see the
processor nowadays. There are evolution
in creating a processor until we get the
form of processor today.
For the first time, computer used vacuum
tube, an electronic device to hold computation.
Vacuum tube is in big size. And one computer
may consist of tens even hundreds of vacuum
tube. That’s why it is no wonder if the first
generation of computer may have a very big size
like a house.
The second generation of computer began
with the invention of transistor to replace the
use of vacuum tube. The effect of this invention
is the reduce on the size of computer. The size
of transistor may be like a peanut-size. That’s
why there is a significant reduce in the size of
computer.
The next generation is the use of Integrated
Circuit (IC) to replace transistor. One IC may
consist of thousands of transistor. Finally the IC
also gets evolution into VLSI which consists of
thousands of IC. That’s about the processor.
The third device is output device. Output
device is any device that can produce
information as the result of computer process.
This information can be displayed in a monitor,
or can be listened via speaker, or can be read
such as in printing form like paper.
Recently there are two kinds of monitor, the
first is CRT monitor which is use electronic tube
that’s why the size is big. The second is LCD.
LCD has slim form since it has flat monitor, the
technology that is used also for notebook and
laptop.
The last device is storage. Actually this
device is used to store or save any information
from a processor. The most common of storage
device are hard disk, flash disk, floppy disk, CDROM
(optical disk), magnetic tape, etc.
The use of computer in daily activities
Recently computers are used by people for the
following purposes:
1. Data Processing. Computers are used in
financial and commercial works such as billing,
inventory control, etc.
2. Scientific Processing. Computers are used to
support science such as nuclear engineering,
mathematic, etc.
3. Multimedia. Examples in this area are for
composing music, creating film animation,
editing film and video, etc.
Task 2
Show whether the followings statements
are true or false (T/F) from Slide 6 - 11.
1. Any kind of instruments that can be used to put
any data into a computer is input device.
2. The form of processor is always the same.
3. The first generation computer used many
vacuum tubes.
4. Today’s processor is using transistor to
replace vacuum tubes.
5. CRD technology is not used for notebook.
Computer Terms
CRT
(Cathode Ray Tube)
LCD
(Liquid Crystal Display)
Vacuum tube
Vacuum tube
Is an electronic device that
uses glass tube to house electronic
circuits. The working of which are
dependent on the vacuum within
the tube. Later, this device was
replaced by transistor.
ENIAC vacuum tube. Integrated Circuit
This is the further
development of transistor.
Consisting hundreds of
transistor in each which
makes computation faster.
Transistor
Is a semiconductor device
used to amplify a signal or open VLSI
and close a circuit. In digital
computers, it functions as an
electronic bridges the gap
between two wires and allows
current fo flow. This device was
invented by William Schockley,
Walten Brattain, and John
Barden. This device has three
feet namely the basis, the
emittor, and the collector.
(Very Large Scale Integration)
Is the packing of hundreds
of thousands of electronic
components on a single
semiconductor chip.
Further Reading
• http://en.wikipedia.org/wiki/Computer
• http://en.wikipedia.org/wiki/Integrated_circuit
• http://www.google.co.id/search?hl=id&defl=en&q
=define:Computer&sa=X&oi=glossary_definition
&ct=title
• http://www.osdata.com/system/physical/basics.h
tm
• http://inventors.about.com/library/blcoindex.htm
Send answer via sms to 8181
Choose a, b, c, or d for the correct answer.
1. Nowadays computer is used for the
following purposes, except ….
a. multimedia
b. scientific processing
c. data processing
d. none of the above
2. The most commonly used input device is ….
a. keyboard c. joystick
b. webcam d. mouse
3. A house size computer is … computer.
a. the second generation
b. the first generation
c. the new generation
d. the third generation
4. This is a picture of ….
a. transistor c. vacuum tube
b. VLSI d. IC
5. Information can be stores in a storing
device such as ….
a. CD-ROM (optical disk) c. monitor
b. track ball d. printer
Meeting 2
Inside a computer
The main part of a
computer to handle the
process is CPU. It stands
for Central Processing
Unit. In this place all the
process goes on. If we
have a deeper look inside
this CPU we can see many
kind of devices attached to
this CPU. On the right is
the box of CPU. Picture of CPU
There are many devices inside the CPU.
Some of them are :
a. Motherboard
This is a printed circuit board (PCB)
which all card or module is attached.
Motherboard is also called with main
board, baseboard, system board, or
planar board.
In Apple computer, it is
called logic board.
b. Processor
Processor is a hardware (sometimes
software) system to handle operations upon
data. For the first time, processor is only a
vacuum tube. Then it undergoes an evolution
becomes transistor, until it reaches the form of
processor as we can see recently.
In personal computers the central processing
unit resides in a single chip called a
microprocessor. When someone refers to the
speed of a computer, the reference is to the
CPU and is measured in megahertz (MHz). But
today the speed of a processor has reached
gigahertz (GHz). Remember the Moore’s Law
about the speed of computer.
There are many companies produces
processor. The main one is Intel. And there are
also AMD and IBM. Below is a processor seen from
the bottom.
c. Memory (RAM)
In order to handle the computation, especially
to access to the most frequent accessed data, a
computer needs a memory. In this case is RAM
(Random Access Memory). The characteristics of
RAM is volatile, meaning that the data that is stored
in memory only available while the computer is turn
on. That’s why you have to save your work before
the computer is turn off.
It is a different case with ROM, which stands
for Read Only Memory. ROM is non-volatile,
meaning that the data is still in ROM even there is
no electricity. Below are some pictures of
computer memory.
Task 1
Answer the following questions from Slide 2 - 6.
1. How many names are there for motherboard?
Mention!
2. What is the measurement for computer speed?
3. Explain the evolution of processor.
4. What is the characteristic of Ram? Explain.
5. ROM is non-volatile. What does it mean?
d. Sound card
Sound card is also known as audio
card. It converts audio signals from a
microphone, audio tape, or some other
sources to digital signals, which can be
stored as a computer audio file. Sound
cards also convert computer audio files to
electrical signals, which you can play
through a speaker or a headphone. The
microphone and the speakers or the
headphones connect to the sound card.
sound card with the ports.
e. VGA card
VGA stands for Video
Graphic Array. This is a
device to handle signal
displayed onto monitor.
f. Internal Modem
Modem stands for modulator and
demodulator. The function is to connect a
computer to the Internet. Modem will transfer a
digital signal from a computer into analog signal.
This process is called modulation. There is
reverse process in the opposite computer, the
receiver. In this computer, the receiver, the
analog signal is received and then converted
into digital signal. This process is known as
demodulation. That’s why a modem does two
processes.
Modem is classified into two kinds. Internal
modem which is placed inside the CPU, called
internal modem.
internal modem
Above is a picture of 56kbps
Conexant Internal modem. This
modem is identified by the chip
where the company creates.
Conexant means the chip is
produced by Conexant
The data transfer from a
modem into the internet or
from the Internet into a
modem is called the speed
of a modem. And it is
measured by kbps, means
‘kilo bit per second’.
The other kind of modem
is external modem which is
placed outside the CPU.
Look at the picture on the
right.
g. Network Interface Card
Network Interface Card or NIC for
shorts. Also known as LAN card. It allows
the computer to be connected to other
computers so that information can be
exchanged between them.
NIC can be identified easily. It has a special
port called RJ-45. RJ means Registered Jack.
And also a led to indicate a data is being
transferred.
Above NIC is connected to other computer
using a cable (wire).
Fortunately, the world is changing. Due
to inefficiency of using cables, people try
not to use cable. This method is called
wireless, means without cable/wire. The
pictures below are LAN Cards without the
need to connect using cable. It is known
as WLAN, Wave LAN, since it uses wave
as a media to transfer data.
Task 2 (Slide 8 – 15)
What do these abbreviations stand for?
1. PCB
2. PCI
3. WLAN
4. LAN
5. Kbps
Complete the following sentence.
6. A sound card can … and ….
7. A modem is used to ….
8. A LAN Card is for ….
FURTHER READINGS
• http://resources.kaboose.com/brain/comples2.
html
• http://computer.howstuffworks.com/pc.htm
• http://www.kids-online.net/learn/c_n_l.html
• http://en.wikipedia.org
• http://www.ied.edu.hk/has/comp/compnent/index
.htm
• http://www.microcenter.com/multimedia/Comput
er_Components_Low/intro_lowband.htm
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Choose a, b, c, or d for the correct answer.
1. CPU stands for ….
a. Central Processed Unit
b. Central Processing Unit
c. Center Processing Unit
d. Central Processor Unit
2. In Apple computer, motherboard is
called ....
a. planar board c. logic board
b. baseboard d. system board
3. Companies that produce processor are
Intel, IBM, and ….
a. AMD c. ADM
b. NIC d. MAD
4. The Speed of a modem is measured by ….
a. MHz c. GHz
b. kbps d. All false
5. “This method is called wireless.” It means
….
a. with wire c. with cable
b. without cable d. lack of wire
Meeting 3
Software and
Operating System
What is Software?
Software is a term to describe a set of
computer programs that perform a
collection of tasks. Software is also a
series of instructions for the computer that
performs a particular task. According to
Wikipedia, the term software was first
used by John W. Tukey in 1958. Software
is divided into some categories. Two major
of them are application software and
system software.
Application software is a generic
name for any software or computer
program. Most of the computer software
excludes system software is application
software. Application software allows enduser
to accomplish one or more specific
(non-related) computer tasks. Some
examples for application software is word
processor such as Microsoft Word 2007,
Open Office Writer, etc.
System software is any computer
software which manages and controls
computer hardware so that application
software can perform a task. System
software will handle and control all
operation process in computer. For
example when someone boots the
computer up, the system software will
perform all operations until the computer is
ready for user. The most important system
software is operating system.
What is Operating System?
An 'operating system' (commonly
abbreviated OS and O/S) is the software
component of a computer system that is
responsible for the management and
coordination of activities and the sharing of the
resources of the computer. The operating
system acts as a host for applications that are
run on the machine. As a host, one of the
purposes of an operating system is to handle the
details of the operation of the hardware. This
relieves application programs from having to
manage these details and makes it easier to
write applications.
Almost all computers, including
handheld computers, desktop computers,
supercomputers, and even video game
consoles, use an operating system of
some type. Some of the oldest models
may however use an embedded operating
system, that may be contained on a
compact disk or other data storage device.
Task 1
Show whether the followings statements are
true or false (T/F) from Slide 2 - 6.
1. Software is also a series of constructions for the
computer that performs a particular task.
2. Most computer software but system software is
application software.
3. System software is any computer software
which manages and controls both computer
hardware and application software.
4. Software is a computer program.
5. Word processor such as Microsoft Word 2007,
Open Office Writer is a system software
Types of Operating System
There are many kinds of operating system.
The most popular one is Windows from
Microsoft Corporation. Microsoft first introduced
an operating environment named Windows in
November 1985 as an add-on to MS-DOS in
response to the growing interest in graphical
user interfaces (GUIs).
Windows Operating System Logo
Other operating system is Mac OS.
Mac OS is the trademarked name for a
series of graphical user interface-based
operating systems developed by Apple
Inc. (formerly Apple Computer, Inc.) for
their Macintosh line of computer
systems. The Macintosh user
experience is credited with popularizing
the graphical user interface.
The original form of what Apple
would later name the "Mac OS" was the
integral and unnamed system software
first introduced in 1984 with the original
Macintosh, usually referred to simply as
the System software.
Recently, there is also an operating
system which has open source license.
The most popular one is Linux. Linux is a
Unix-like computer operating system
family which uses the Linux kernel. Linux
is one of the most prominent examples of
free software and open source
development; typically all the underlying
source code can be freely modified,
used, and redistributed by anyone. For
the first time Linux kernel is created by
Linus Torvalds.
Nowadays, Linux has abundant variant called
distributions. Below are some of Linux distributions
in ranking per October 2008 (you may refer to
http://www.distrowatch.com) :Ubuntu, openSUSE, Mint,
Fedora, PCLinuxOS, Debian, Mandriva, and more.
Ubuntu has been the most popular Linux
distributions for the last few years, since it has
unique feature that most people need. The feature
is ‘live CD’ which is enable someone to try Ubuntu
from Ubuntu CD without installing Ubuntu on to
harddisk. You may request Ubuntu CD for free at
http://shipit.ubuntu.com.
Task 2
Match the terms with the definition!
1. Computer Task
2. Boot the computer up
3. Host
4. Handheld computer
5. Desktop computer
6. Supercomputer
7. Video game console
8. GUI
9. CLI
Here are the Definition
A. Turn the computer on
B. a machine specified for playing game,
such as Play station, Nintendo, Xbox, etc
C. a computer that is used on a desk
D. Central
E. Graphical User Interface. It is an
interface for user using graphical mode.
In this mode user can give a command to
a computer by activating a mouse
pointer. For example clicking a button
Save to save a document.
E. Something that a computer has to do.
F. Command Line Interface. It is the
opposite meaning of GUI. In CLI mode
user can give a command to a computer
by typing a command. It works on DOS
era. For example when a user try to
delete a file, he has to type a command:
Del a_file_name.txt
G. a computer to handle heavy computation
H. a computer that easy to carry
• FURTHER READINGS
• http://shipit.ubuntu.com
• http://en.wikipedia.org/wiki/Computer_software
• http://en.wikipedia.org/wiki/Application_software
• http://en.wikipedia.org/wiki/Operating_system
• http://en.wikipedia.org/wiki/Solaris_(operating_s
ystem)
• http://en.wikipedia.org/wiki/Linux
• http://en.wikipedia.org/wiki/Microsoft_Windows
• http://en.wikipedia.org/wiki/Mac_OS
• http://www.distrowatch.com
Send answer via sms to 8181
Choose a, b, c, or d for the correct answer.
1. The two major software are ….
a. application and system software
b. application and instructional software
b. system software and command
c. application software and processor
2. The term software was first used by … in
1958.
a. John W. Turkey c. John M. Tukey
b. John W. Tukey d. Jack W. Tukey
3. An open source software means it is ….
a. freely modified c. prominent
b. freely used d. freely redistributed
by anyone
4. These are types of operating system available
to users, except ….
a. Windows c. Mac OS
b. GUIs d. Linux
5. Word processor such as Microsoft Word 2007
and Open Office Writer are examples of ….
a. system software
b. application software
c. office application
d. OS
Meeting 4
Software and
Programming Language
A Software is Created by Programming
A set of computer consists of metal,
plastic, and other physical devices which
is called hardware. This hardware is no
use without software. Software is a term to
describe a set of computer programs that
perform a collection of tasks. Software is
also a series of instructions for the
computer that performs a particular task.
Software is created by a process called
programming or computer programming. This
process can also be called by coding which is a
process of writing, testing, debugging, and
maintain a source code of computer programs.
In programming process, a programmer (a
person who writes computer program) must
write all code in a text editor with no error at all.
He has to write from first line until last line of
code. All of the code from first line until last line
is called source code. This is the actual form of
computer instructions which give a computer an
instruction of what to do.
After that, a programmer must compile the
source code. A tool to compile is a compiler.
This process is called compilation, that is
transforming a source code into binary file like
executable file. Mostly, a programmer will face
error during compilation and the source code
cannot be transformed into binary file. So a
programmer will look for the error and fix it.
This action is called debugging, that is
finding and fixing error code in all of the source
code. A tool for debugging is called debugger.
The action of compilation and debugging will
repeat and repeat, again and again until there is
no error at all in the source code.
If we resume the above process would be like this:
a. Step one: Writing a code
b. Step two: Compilation
c. Step three: Debugging
d. Step four: The result is binary file
For the first time in computer programming, text
editor, compiler, and debugger, are separated one
another. But in advanced era of computer
programming, those tools are integrated. So a
programmer will be more comfortable and easier in
creating a program.
Below are a picture of Borland Delphi 7, an
integrated tool for programming.
Task 1
Find the synonym from the passage (Slide
2 – 5) which mean the same as:
1. Mistake
2. Collection
3. Changing completely
4. Do
5. Instrument/device
6. The most modern
7. Pleasant
8. Search
9. Summarize
10. Coding
A picture of computer source code
in Delphi language
A picture about an integrated
tool for programming
Kinds of Programming Language
1. Pascal from Borland
2. Borland Delphi from Borland
3. BASIC from Microsoft
4. Microsoft Visual Basic from
Microsoft
5. FoxPro
6. Java from Sun Microsystem
7. Phyton
8. C / C++
9. PROLOG
10.FORTRAN
11.COBOL
12.Assembler, etc.
Picture. Splash screen
of Borland Delphi 8
Task 2
Match the terms with the definition.
1. Programmer =
2. Debugger =
3. Coding =
4. Compiler =
The definitions
a. a tool to compile a source code into binary file
b. a person who creates and writes a program.
c. a tool to find and fix an error code in a source
code
d. programming = computer programming
FURTHER READINGS
• http://en.wikipedia.org/wiki/Programming
• http://en.wikipedia.org/wiki/Software
• http://programming.wikia.com/wiki/Main_P
age
• http://en.wikipedia.org/wiki/List_of_basic_c
omputer_programming_topics
• http://en.wikipedia.org/wiki/Software_engin
eering
Send answer via sms to 8181
Choose a, b, c, or d for the correct answer.
1. In programming process, the first step is ….
a. compilation c. writing a code
b. debugging d. binary file
2. The physical devices in a computer are ….
a. tools c. software
b. hardware d. none of the above
3. A programmer must compile the source
code by using ….
a. compiler c. collector
b. transformer d. bugger
4. Acts of finding and fixing error code in all
of the source code is called ….
a. debugging c. bugging
b. compiler d. decoding
5. The following is a programming language
from Sun Microsystems.
a. Pascal c. BASIC
b. JAVA d. Borland
Meeting 5
Malicious Software
In computer world, there is also a software which is
created to do something bad and to perform criminal
intension. This kind of software is called malicious
software or malware. Malicious software can be
divided into some categories:
a. Virus
b. Worm
c. Trojan Horse
d. Logic bomb
e. Time bomb
f. Malicious code, etc
But the most important categories are virus, worm,
and Trojan horse. All of them can be identified by their
replication.
VIRUS
Virus is a software that can replicate
by injecting or infecting its own code
into other file. By its way to infect
other file, virus can be divided into
three categories:
a. Overwriting
b. Appending
c. Prepending
Virus can be created using programming
language since virus is actually a program.
Anybody can write a program and run it. But the
important point in programming a virus is a code
for replicating a virus.
Other way in creating a virus is using a tool.
This is the simplest and easiest way in creating
a virus. This kind of tool is called virus generator
or virus creator, or virus kit, or virus constructor,
etc. You can search this tool using Google with
those keywords. Using virus generator, anybody
without any programming skill can create a virus,
even if he is a new comer in computer world!
On the left is a
picture about
virus generator
called Microsoft
Macro Virus
Generator.
Below is a virus
generator called Walrus
Macro Virus Generator.
As you can see in the
picture, the way to create
a virus using virus
generator is just selecting
some options and then hit
the button Generate. A
new virus is ready for
you, just as instant as
creating instant noodles.
b. WORM
Worm is also a kind of malicious
software. It is different from virus which is
worm can not inject of infect other files. A
worm is a software which replicates by
creating its own copy. And without
infecting other file.
Worm actually spreads through a
network or the Internet using email. Below
is a sample of worm called I Love You.
Worm I Love You spreads through the
Internet as an email attachment. Pay
attention at the attachment LOVELETTER-
FOR-YOU.TXT.Vbs.
Usually worm will do something
tricky to cheat email receiver. The
first is using double file extension.
At the left sample, worm I Love
You uses two extension, those are
TXT.VBS. The second trick is
using social engineering. At the
above sample, the worm uses a
name “I LOVE YOU” which might
interested to every email receiver.
Who doesn’t need love? So, the
effect of these tricks are any body
–the email receiver- will click that
attachment which is actually a
worm code.
Task 1
(From Slide 2 – 9) What do the followings
refer to (replace)?
1. Slide 2, line 13: Them _____
2. Slide 3, line 2: its _____
3. Slide 5, line 3: it _____
4. Slide 5, line 7: This _____
5. Slide 5, line 13: he _____
6. Slide 8, line 2: It _____
c. TROJAN HORSE
Trojan horse is derived from ancient Greek. Trojan
Horse is a program that looks like a good program but
actually contains destructive code or destructive
feature. Trojan horse is different from virus and worm,
trojan horse can not replicate and cannot infect other
file.
There are many kind of trojan horse. Below are
some of them:
a. Password stealer
b. Keylogger
c. Fake Program
d. Anonymous emailer
e. Remote monitoring
f. Remote administrator, etc
Below are some examples of Trojan horse
1. Back Orifice created by a group called CDC
2. Mata-Mata created by ÇäkrabiRâwÄ
3. SubSeven created by Mobman
4. NetBus created by Carl Fredrik Neikter
5. Deep Throat created by DarkLIGHT
6. Barok created by Onel de Guzman
Left is a picture of
trojan hose Back Orifice.
Below is a picture of
Mata-Mata trojan hose.
This is a sample trojan of
keylogging tool.
Below is a picture of Sub
Seven.
Task 2
Match each definition with the correct term!
1. ___ is a tool for creating a virus instantly.
2. ___ is a program designed for stealing password.
3. ___ is a program designed to record all keyboard
keystroke into a log file.
4. ___ is a program imitating a real program but it has
destructive features that makes fun for the creator.
5. ___ is a program for sending email without known its
sender (anonymous).
6. ___ is a program that can control other computer
remotely.
7. ___ is a program that can monitor other computer
remotely.
Here are the terms.
a. Fake program
b. Virus generator
c. Remote
administrator
d. Password stealer
e. Remote monitoring
f. Keylogger
g. Anonymous emailer
FURTHER READINGS
• http://id.wikipedia.org/wiki/Virus_komputer
• http://en.wikipedia.org/wiki/Computer_virus
• http://www.microsoft.com/protect/computer/basics/virus.mspx
• http://compnetworking.about.com/cs/worldwideweb/g/bldef_w
orm.htm
• http://www.tech-faq.com/computer-worm-virus.shtml
• http://en.wikipedia.org/wiki/Computer_worm
• http://www.icir.org/vern/papers/taxonomy.pdf
• http://www.howstuffworks.com/virus.htm
• http://en.wikipedia.org/wiki/Trojan_horse_(computing)
• http://www.webopedia.com/DidYouKnow/Internet/2004/virus.a
sp
• http://y2u.co.uk/Knowledge_Information/Technology/RN_Com
puter_Trojan_Horses_A1.htm
• http://id.wikipedia.org/wiki/Trojan_horse
Send answer via sms
Choose a, b, c, or d for the correct answer.
1. One of these is not a malware.
a. worm c. Trojan Horse
b. Logic bomb d. Win Vista
2. All of them can be identified by their ….
a. replication c. multiplication
b. identification d. none of the above
3. By its way to infect other file, virus can be
divided into … categories.
a. one c. two
b. three d. four
4. The simplest and easiest way in creating
virus is by using a tool called ….
a. virus generator c. virus copier
b. virus instructor d. virus emulator
5. … actually spreads through a network or
the Internet using email.
a. worm c. Trojan Horse
b. Time Bomb d. Virus
Meeting 6
Hardware
Hardware is physical equipment of
computer system. Hardware can be
divided into two categories: Input Device
and Output Device
INPUT DEVICE
Input device is computer device that is
used to input data into computer system.
Input device can be divided into some
categories:
1. Text input devices
Such as keyboard, a device to input text and
characters by depressing buttons (referred to
as keys), similar to a typewriter. The most
common English-language key layout is the
QWERTY layout. Below is a picture of a
keyboard using QWERTY layout.
Other alternative layout is DVORAK layout
as seen in this picture.
Other alternatives keyboard layout is
QWERTZ layout which is used in Germany and
much of Central Europe, and AZERTY layout
which is used France, Belgium, and some
neighbouring countries.
2. Pointing devices
The most common pointing device is mouse. In
computing, a mouse (plural mice or mouse
devices) is a pointing device that functions by
detecting two-dimensional motion relative to its
supporting surface. Physically, a mouse consists
of an object held under one of the user's hands,
with one or more buttons, other elements, such as
"wheels", or extra buttons.
The mouse's motion is typically translated into
the motion of a pointer on a display,
which allows for fine control of
a Graphical User Interface. Here
is a picture of a modern mouse.
Other alternative of pointing device is
trackball, a pointing device consisting of an
exposed protruding ball housed in a socket that
detects rotation about two axes. The trackball
was invented by Tom Cranston and Fred
Longstaff as part of the Royal Canadian Navy's
DATAR system in 1952[1], eleven years before
the mouse was invented. Below is a picture of a
trackball.
3. Gaming devices
One example of
gaming device is a
joystick. A joystick is
a general control
device that consists of
a handheld stick that
pivots around one end,
to detect angles in two
or three dimensions.
4. Image, Video input devices
There are two common
input devices in this type.
First is Image scanner, a
device that provides input by
analyzing images, printed
text, handwriting, or an
object. Below is a picture of
image scanner.
Second type is a webcam. Webcams
are video capturing devices connected to
computers or computer networks, often
using USB or, if they connect to networks,
ethernet or Wi-Fi. They are well-known for
their low manufacturing costs and flexible
applications. Below is a picture of a
webcam.
5. Audio input devices
One example of audio input device is a
microphone. Microphone sometimes referred
to as a mic or mike, is an acoustic-to-electric
transducer or sensor that converts sound into
an electrical signal. Microphones are used in
many applications such as telephones, tape
recorders, hearing aids, motion picture
production, live and recorded audio
engineering, in radio and television
broadcasting and in computers for recording
voice, VoIP, and for non-acoustic purposes
such as ultrasonic checking.
Task 1
Answer the following questions based on
slide 2 – 10.
1. What are the categories of hardware?
2. How many types of input device are there?
Mention.
3. What is the function of a scanner?
4. Where is QWERTZ keyboard layout used?
5. How does a microphone work?
6. Why is webcam well-known?
OUTPUT DEVICE
1. Image, Video Output Devices
First example is a printer. In computing, a
printer is a peripheral which produces a hard
copy (permanent human-readable text and/or
graphics) of documents stored in electronic form,
usually on physical print media such as paper or
transparencies. Many printers are primarily used
as local peripherals, and are attached by a
printer cable or, in most newer printers, a USB
cable to a computer which serves as a
document source.
Some printers, commonly known as network
printers, have built-in network interfaces
(typically wireless or Ethernet), and can serve as
a hardcopy device for any user on the network.
Individual printers are often designed to support
both local and network connected users at the
same time.
Second Example is a monitor. A visual
display unit, often called simply a monitor or
display, is a piece of electrical equipment which
displays images generated from the video output
of devices such as computers, without producing
a permanent record.
2. Audio Output Devices
Speakers. Computer speakers, or multimedia
speakers, are external speakers, commonly equipped
with a low-power internal amplifier.
Headsets. Headphones are a pair of small
loudspeakers, or less commonly a single speaker, with
a way of holding them close to a user's ears and a
means of connecting them to a signal source such as
an audio amplifier, radio or CD player. They are also
known as earphones, ear buds, stereo phones,
headsets or, informally cans. In the context of
telecommunication, the term headset is used to
describe a combination of headphone and microphone
used for two-way communication, for example with a
telephone.
Task 2
Find the synonym of these words or
phrases in the text of slide 12-14.
1. Lasting __________
2. Fasten __________
3. Familiar __________
4. Shows __________
5. Origin __________
6. Utilized __________
7. Instance __________
8. Wire __________
9. Joining __________
10. Picture __________
Computer terms:
Hardcopy device is a device to print onto a permanent
device such as a paper.
Flexible application is an application that is easy to use.
Feature is additional tool to handle a function.
FURTHER READINGS
• http://en.wikipedia.org/wiki/Computer_hardware#Input
• http://en.wikipedia.org/wiki/Trackball
• http://en.wikipedia.org/wiki/Joystick
• http://en.wikipedia.org/wiki/Gamepad
• http://en.wikipedia.org/wiki/Game_controller
• http://en.wikipedia.org/wiki/Image_scanner
Send answer via sms to 8181
Choose a, b, c, or d for the correct answer.
1. Which is an example of a pointing device?
a. joystick c. trackball
b. scanner d. webcam
2. AZERTY keyboard layout is used in ….
a. France c. Belgium
b. both a and b d. All Europe
3. Computer speakers are commonly
equipped with a low-power … amplifier.
a. internal c. external
b. visual d. internal & external
4. The trackball was invented by ….
a. Tom Cruise c. Tom Cranston
b. Tom Dooley d. Tom Longstaff
5. Visual Display Unit is another term for ….
a. printer c. scanner
b. monitor d. television
Meeting 9
Computer Network
Definition of
computer networks
A computer network is a group of
interconnected computers. Networks may be
classified according to a wide variety of
characteristics. The benefit of a computer
network are: Sharing hardware resources easily
and Sharing information easily.
A network is a collection of computers
connected to each other. The network allows
computers to communicate with each other and
share resources and information. The Advanced
Research Projects Agency (ARPA) designed
"Advanced Research Projects Agency Network"
(ARPANET) for the United States Department of
Defense. It was the first computer network in the
world in late 1960's and early 1970's.
Types of computer networks
1. Local-area networks (LANs): The computers
are geographically close together (that is, in the
same building).
2. Wide-area networks (WANs): The computers
are farther apart and are connected by
telephone lines or radio waves.
3. Campus-area networks (CANs): The
computers are within a limited geographic area,
such as a campus or military base.
4. Metropolitan-area networks (MANs): A data
network designed for a town or city.
5. Home-area networks (HANs): A network
contained within a user's home that connects a
person's digital devices.
The following characteristics are used to categorize
different types of networks:
1. topology: The geometric arrangement of a computer
system. Common topologies include a bus, star, and
ring.
2. protocol: The protocol defines a common set of rules
and signals that computers on the network use to
communicate. Two of the most popular protocols for
LANs is called Ethernet and the IBM token-ring network.
3. architecture: Networks can be broadly classified as
using either a peer-to-peer or client/server architecture.
Computers on a network are sometimes called nodes.
Computers and devices that allocate resources for a
network are called servers.
Networks Topology
www.webopedia.com
What do we need to create
a computer network?
There are many kinds of devices to create a
computer network. For a basic computer
network we would need:
1. Network Interface Cards
A network card, network adapter or NIC
(network interface card) is a piece of computer
hardware designed to allow computers to
communicate over a computer network
NIC can be identified easily. It has a special port
called RJ-45. RJ means Registered Jack. And also a led
to indicate a data is being transferred.
2. Repeaters
A repeater is an electronic device that receives a signal
and retransmits it at a higher power level, or to the other
side of an obstruction, so that the signal can cover
longer distances without degradation.
3. Hub
A hub contains multiple ports. When a
packet arrives at one port, it is copied to all the
ports of the hub for transmission. When the
packets are copied, the destination address in
the frame does not change to a broadcast
address. Below is a picture of 4-port ethernet
hub.
Above is a network switch
Task 1
Which words in the slides have the
opposite meaning to the following?
1. Narrow
2. Disadvantage
3. Hard/difficult
4. The last
5. Few
6. Sends
7. Single port
8. Above
9. Disconnected
10. Shorter
Task 2
Answer these questions based on
slide 2-5.
1. What is meant by a network?
2. What are the advantages of a network?
3. How do we create a basic network?
4. Who create the first network?
5. How to categorize different types of
networks?
COMPUTER TERMS
• Network is a set of items connected together into one
unit
• Port in a hub or switch is a slot to connect a hub or
switch to other network device
FURTHER READINGS
• http://en.wikipedia.org/wiki/Computer_networks
• http://en.wikipedia.org/wiki/Network_hub
• http://en.wikipedia.org/wiki/Repeater
• http://www.webopedia.com/TERM/N/network.html
• http://www.uaf.edu/toolik/Reports/Report03/CommsSlid
es-SRI.ppt
• http://www.cs.ucr.edu/~weesan/cs6/03_basic_computer
_network.ppt
Send answer via sms to 8181
1. A NIC, …, and a hub are needed to
create a basic network.
a. repeaters c. modulator
b. socket d. jack
2. The network allows computers to … with
each other.
a. commune c. collaborate
b. coordinate d. communicate
3. NIC can be identified easily. It has a
special port called ….
a. AJ-45 c. RJ-45
b. RJ-54 d. AJ-54
4. Another term for NIC is ….
a. repeaters c. adapter
b. network adapter d. modem
5. What does ARPA stand for?
a. Advance Research Projects Agency
b. Advance Research Projects Affair
c. Advanced Research Projects Agency
d. Advanced Research Projects Affair
Steganography
What is steganography
Steganography is the art and science
of writing hidden messages in such a way
that no-one apart from the sender and
intended recipient even realizes there is a
hidden message, a form of security
through obscurity. By contrast,
cryptography obscures the meaning of a
message, but it does not conceal the fact
that there is a message.
Generally, a steganographic message will appear
to be something else: a picture, an article, a shopping
list, or some other message. This apparent message
is the covertext. For instance, a message may be
hidden by using invisible ink between the visible lines
of innocuous documents.
The advantage of steganography over
cryptography alone is that messages do not attract
attention to themselves, to messengers, or to
recipients. An unhidden coded message, no matter
how unbreakable it is, will arouse suspicion and may
in itself be incriminating, as in countries where
encryption is illegal. Often, steganography and
cryptography are used together to ensure security of
the covered message.
Someone who is expert in steganography is
called steganalyst.
History of steganography
The word steganography is of Greek origin
and means "covered, or hidden writing". Its
ancient origins can be traced back to 440 BC.
Herodotus mentions two examples of
steganography in The Histories of Herodotus.
Demaratus sent a warning about a forthcoming
attack to Greece by writing it on a wooden panel
and covering it in wax. Wax tablets were in
common use then as re-usable writing surfaces,
sometimes used for shorthand.
Another ancient example is that of Histiaeus,
who shaved the head of his most trusted slave
and tattooed a message on it. After his hair had
grown the message was hidden. The purpose
was to instigate a revolt against the Persians.
Task 1
Check your understanding.
1. What is steganography for?
2. What is covertext?
3. Why is steganography better than
cryptography?
4. Who sent a warning to Greece by using
steganography?
5. How did Histiaeus apply the
steganography technique?
Some Techniques of Steganography
1. Writing a secret message using invisible ink.
2. Hidden messages on messenger's body: also
in ancient Greece. Herodotus tells the story
of a message tattooed on a slave's shaved
head, hidden by the growth of his hair, and
exposed by shaving his head again.
The message allegedly carried a warning
to Greece about Persian invasion plans.
This method has obvious drawbacks:
a. It is impossible to send a message as quickly
as the slave can travel, because it takes
months to grow hair.
b. A slave can only be used once for this
purpose. (This is why slaves were used: they
were considered expendable).
3. A picture of a message in microdots or
microfilms.
4. In computer era, steganography can be done by
inserting a secret document into other
document. Any document can be used as a
media, for example text file, picture file, or
multimedia file such as mp3 or video file.
Practice
• Prepare an image for cover image.
• Prepare a secret image to be hidden.
• Go to this site
http://incoherency.co.uk/hideimage.php
• Hit button Go!
Task 2
Find the term in the passage which have
meaning of the following (Slide 7-9).
1. Colored liquid material that is hidden or cannot
be seen.
2. So very old
3. Removing hair or beard
4. Must not be known by others
5. A person who is owned by and must served
someone
6. A tiny sized dot
7. Coming to conquest or rule
8. Disadvantage
COMPUTER TERMS
• Cover text = a text or a messages that is displayed to a user
• Encryption = a process converting plain text into cipher text
FURTHER READINGS
• http://www.dmoz.org/Computers/Security/Products_and_Tools/Crypt
ography/Steganography//
• http://petitcolas.net/fabien/steganography/image_downgrading/index
.html
• http://www.fbi.gov/hq/lab/fsc/backissu/july2004/research/2004_03_r
esearch01.htm
• http://www.jjtc.com/Steganography
• http://www.citi.umich.edu/techreports/reports/citi-tr-01-11.pdf
• http://www.spy-hunter.com/stego.html
• http://www.datahide.com/BPCSe/Articles/Ref-6.SPIE98.pdf
• http://blog.maxant.co.uk/pebble/2007/07/19/1184876280000.html
Send answer via sms to 8181
Choose a, b, c, or d for the correct answer.
1. Steganography is the art and science of
writing … messages.
a. readable c. computer
b. hidden d. picture
2. Another secret coding technique besides
steganography is ….
a. cryptonite c. cryptic
b. cryptography d. steganalyst
3. Steganography comes from … language.
a. Greek c. Greece
b. Latin d. French
4. Writing a hidden message can use an … ink.
a. invincible c. invisible
b. inevitable d. indispensable
5. This document can be used as a media in
steganography, except ….
a. text file c. picture file
b. mp3 or video file d. none of the above
Meeting 11
Cryptography
What is cryptography
The term cryptography is derived from Greek,
kryptos means “hidden” or “secret” and graphy
means “writing”. So, cryptography is the practice
and study of creating a secret information.
Cryptography works by Cryptography is a part of
mathematics and computer science.
Cryptography is used in applications present
in technologically advanced societies; examples
include the security of ATM cards, computer
passwords, and electronic commerce, which all
depend on cryptography. In short we can say that
cryptography is needed to secure a secret
document. A person who is master in
cryptography is called cryptographer.
How cryptography works
For example someone has a secret
document to secure. Any document can be
secured using cryptography. For example we
have to secure the word “Read” using
cryptography. The word “Read” in cryptography
is called Plain text. Using a set of rule called
algorithm, the plain text is changed into cipher
text. This process is called encryption. The result
of this encryption process is the word “Uhdg”.
This is the cipher text.
A set of rule (algorithm) that is used in
encryption can be different. There are
many algorithm used in encryption. At the
above example we use Caesar Cipher
algorithm that is used by Julius Caesar to
secure his document.
The reverse process of encryption is called
decryption. The input is a cipher text. And the
result of decryption process is plain text.
Task 2
Show whether the followings statements
are true or false (T/F) from Slide 2 - 5.
1. Cryptography is the practice and study of
creating a secret information.
2. Not all document can be secured using
cryptography.
3. Using a set of rule called algebra, the plain
text is changed into cipher text.
4. The word “kryptos” is a Latin origin.
5. The reverse process of encryption is called
decryption.
History of cryptography
Cryptography is already used since ancient
era. Julius Caesar used cryptography to secure
his message from his enemy. He replaced a
character with its next three character. For
example a character ‘A’ in alphabet will be
replaced by character ‘D’. And so on. See the list
below of Julius Caesar algorithm.
• Plain text : a b c d e f g h I j k l m n o p q r
s t u v w x y z
• Cipher Text : d e f g h I j k l m n o p q r s t u
v w x y z a b c
In the era of World War II,
German Nazi was also used
cryptography to secure its
message. Nazi used a machine
called Enigma to encrypt and
decrypt the messages. In this
way Nazi thought its message
would be difficult to break by US
and its allies. Below is a picture
of Enigma used by Nazi.
Unfortunately the algorithm of Enigma can
be broken by US army.
In computer technology, cryptography
is still used to secure a computer data or
document. For example in ATM machine,
computer passwords, and also in
electronic commerce. Using computer
technology someone can use many
sophisticated algorithm for example RSA,
DES, and PGP.
COMPUTER TERMS
• Plain text = a text that can be read by anybody.
This text is not secured yet.
• Cipher text = a secret text resulting from
encryption process.
• Algorithm = a set of rule to encrypt a document.
• Enigma = a machine like typewriter that is used
by Nazi during World War II to secure
a document before transmitted.
• Cryptographer = a person who is master in
cryptography.
Task 2
Figure out this message.
“BRX KDYH MXVW GLVFRYHUHD WKH
DQFLHQW VHFUHW FRGLQJ FDOOHG
MXOLXV FDHVDU DOJRULWKP”
What does it say?
___________________________________
___________________________________
mhtirogla raseaC suiluJ esU
FURTHER READINGS
• http://en.wikipedia.org/wiki/Cryptography
• http://en.wikipedia.org/wiki/Cryptography_Classification
• http://en.wikipedia.org/wiki/Encyclopedia_of_Cryptography_and_Security
• http://en.wikipedia.org/wiki/Japanese_cryptology_from_the_1500s_to_Meiji
• http://en.wikipedia.org/wiki/List_of_important_publications_in_computer_science#Cry
ptography
• http://www.merriam-webster.com/dictionary/cryptology/
• http://www.csrc.nist.gov/publications/fips/fips197/fips-197.pdf
• http://www.cesg.gov.uk/site/publications/media/notense.pdf
• http://citeseer.ist.psu.edu/cache/papers/cs/22094/http:zSzzSzeprint.iacr.orgzSz2001z
Sz056.pdf/junod01complexity.pdf
• http://www.rsasecurity.com/rsalabs/node.asp?id=2152
• http://www.ieee-security.org/Cipher/Newsbriefs/1996/960214.zimmerman.html
• http://www.schneier.com/crypto-gram-0006.html#DES
• http://scholar.google.com/url?sa=U&q=http://www.springerlink.com/index/K54H077N
P8714058.pdf
• http://www.cacr.math.uwaterloo.ca/hac/
• http://www.cryptool.org/download/CrypToolPresentation-en-1_4_20.pdf
• http://www.rsasecurity.com/rsalabs/node.asp?id=2152
• http://www.pawlan.com/Monica/crypto/
• http://www.nsa.gov/kids/
Send answer via sms 8181
Choose a, b, c, or d for the correct answer.
1. Nazi used a machine called … to encrypt
and decrypt the messages.
a. Sigma c. Encarta
b. Enigma d. all false
2. A cryptographer is … who is master in
cryptography.
a. Something c. someone
b. anything d. anyone
3. “Graphy” is a Greek word means….
a. spoken c. uttered
b. written d. hidden
4. Cryptography is needed to … a secret
document.
a. secure c. save
b. keep d. run
5. A secret text resulting from encryption
process is called ….
a. plain text c. code text
b. cyber text d. cipher text
Meeting 12
The Internet
Internet stands for: Internetworked Networks
The Internet is a worldwide connection of
millions of computers connected to thousands of
different networks. These computers
"communicate" that is, share, exchange, and
transmit data to another computer on the same
or another network.
Nobody owns or controls the Internet. It is a
global information system similar in some
respects to telephone networks that allow
anybody to call any other number anytime,
anywhere.
a. Internet Services
The Internet has several component applications. These
include:
1. Telnet - terminal emulation - Allows a user on one
computer to log onto a remote computer and run
software on that remote computer as if it were on the
user's local computer
2. FTP – File Transfer Protocol - Allows users to upload
and download files from other computers
3. EDI – Electronic Data Interchange - Allows for
electronic transfer of data between companies over
the Internet
4. IRC – Internet Relay Chat - Allows people connected
over the Internet to participate in discussions. It allows
people to converse in "real time," people may actually
see you type your questions and responses.
6. Email – Electronic Mail, allows people to send and
receive electronic messages.
7. Newsgroup - This is the Internet equivalent of a
discussion group or an electronic bulletin board. There
are newsgroups for every conceivable topic and more,
from educational technology and Brazil culture to stamp
collecting and mountaineering. Computer newsgroups
start with comp as in comp.apps.spreadsheets. while
recreational newsgroups start with rec as in
rec.arts.cinema. The others are alt for alternate, soc for
social, sci for science, and news for news.
8. World Wide Web is a vast, ever-expanding collection
of online documents and information formatted in
Hypertext Markup Language (HTML) distributed over
the Internet. It is a software application that uses the
Internet.
b. Internet address domain
Each computer on the Internet is called an Internet
host or a host machine. Each host machine has a
special Internet protocol address (IP address) that
uniquely identifies that computer. IP addresses were
never designed to be seen by human eyes. They are an
address that is interpreted by a computer. An example of
an IP address is:
205.213.164.10
Since numbers are easy for a computer to work with but
difficult for humans, most host machines have a Domain
Name Service (DNS) address. For instance, the domain
name service address of the IP address listed above is:
depts.alverno.edu
The most common Top Level Domains (TLD)
are:
TLD Name Type of Organization
.com A commercial organization in
.edu An educational site in the US
.gov A government agency in the US
.mil A military site in the US
.net A network site
.org A nonprofit organization
Other TLD names identify geographical
locations by country – such as:
TLD Name Location by country
.au Australia
.ca Canada
.dk Denmark
.fr France
.de Germany
.uk Great Britain
.hk Hong Kong
.hu Hungary
.ie Ireland
.id Indonesia
Newly added Top-Level Domains
include:
TLD Name Type of
Organization
.biz Businesses
.info For all users
TLD scheduled to be added soon include:
TLD Name Type of Organization
.aero For the air-transport
industry
.coop For cooperatives
Top-Level Domain Names help the user to
identify what type of site they are visiting.
.museum For museums
.name For individuals
.pro For professionals
c. Netiquette
There are guidelines on how one must
behave in cyberspace. In the Internet
these responsibilities are defined by what
is called Netiquette. There are different
versions of Netiquette on the Web, the
following is an example of netiquette.
10 Commandments of Computer Use
by Computer Ethics Institute in
Washington D.C.
1. Thou shalt not use a computer to harm
other people
2. Thou shalt not interfere with other
people's computer work
3. Thou shalt not snoop around in other people's computer
files
4. Thou shalt not use a computer to steal
5. Thou shalt not use a computer to bear false witness
6. Thou shalt not copy or use proprietary software for
which you have not paid
7. Thou shalt not use other people's computer resources
without authorization or proper compensation
8. Thou shalt not appropriate other people's intellectual
output
9. Thou shalt think about consequences of the program
you are writing or the system you are designing
10. Thou shalt always use a computer in ways that ensure
consideration and respect for your fellow humans.
Task 1
Answer these questions.
1. In a network, computers ‘communicate’ with
each other. What does it mean?
2. If you want to upload and download files from
other computers, what component application do
you need?
3. What is the guidelines on how someone must
behave in cyberspace called?
4. Can we copy paste other people’s intellectual
output and claim it as our idea?
5. www.spiegel.de/international/business
www.kompass.ie
In what country is the location of the website?
Challenge!
Match the top level domain with the correct
description in 10 seconds!
____1) .com A. US Educational institution
____2) .gov B. A non-profit or not-for-profit
institution
____3) .org C. US Governmental agency
____4) .mil D. A company or business
____5) .edu E. US Military
Task 2
Take home assignment
In a group, translate the 10
Commandments of Computer Use by
Computer Ethics Institute in
Washington D.C.
Further readings
• http://en.wikipedia.org/wiki/Internet
• http://www.comptechdoc.org/basic/basictut
/
• http://dragon.ep.usm.edu/~it365/module/In
ternet/Internet.htm
• http://depts.alverno.edu/cil/mod1/webtutori
al/internet.html
Send the answer via sms to 8181
Choose a, b, c, or d for the correct
answer.
1. This component application allows
people connected over the Internet to
participate in discussions.
a. Telnet c. IRC
b. FTP d. EDI
2. This website is owned by a nonprofit
institution.
a. www.cars.com c. www.carmagazine.co.uk
b. www.car.org d. www.carzone.ie
3. This website is a government agency.
a. ocw.mit.edu
b. www.language-learning.net
c. training.fema.gov
d. www.carecourses.com
4. The Netiquette number 4 states that “You
shall not use a computer to ….”
a. steal c. break
b. hack d. deal
5. Recreational newsgroups start with ….
a. alt c. soc
b. rec d. sci
Meeting 13
E-mail
Electronic mail, often abbreviated as email,
email, or eMail, is any method of
creating, transmitting, or storing primarily
text-based human communications with
digital communications systems. Unlike
conventional mail, email is much faster
(conventional mail is sometimes called
"snail mail" by email users).
Email has both similarities and
differences with more conventional postal
services. First, messages are posted
electronically to individuals at specific
addresses much like conventional mail.
The address denotes the computer that
the individual employs as a mail server. A
mail server is like a local post office: it is a
computer that sends and receives
electronic mail for a specific network.
This is how email works
An email message is made up of several
parts. They include:
header - It contains information about the
sender, the routing and the time of the message.
The header always contains a subject line. This
is a very important part of the message and
you should always include a subject line. Some
folks sort their messages by subject, so it is rude
to not include a subject! The subject line
indicates the purpose or content of the message
message body, where you write your message
signature, which identifies the sender. This part
is optional and must be set up inside of your
email software
Header fields
The message header usually includes at least the
following fields:
From: The e-mail address of the sender
To: The e-mail address of recipient
Subject: Topic of message
Date: The local time and date when the message was
written
Cc: carbon copy, adopted from business
communication protocol when typewriters ruled the
day
Bcc: Blind Carbon Copy, when recipient
does not need to know who else got a copy
of the message. May or may not appear in
sender's file copy depending on e-mail
software used
A picture of an email page
The usefulness of e-mail is being threatened
by four phenomena:
a. E-mail bombardment, an e-mail bomb is a
form of net abuse consisting of sending huge
volumes of e-mail to an address in an attempt
to overflow the mailbox or overwhelm the
server.
b. spamming, unsolicited commercial (or bulk) email
results in information overload for many
computer users who receive such email each
day
c. phishing, process of attempting to
acquire sensitive information such as
usernames, passwords and credit card
details by masquerading as a trustworthy
entity in an electronic communication.
d. E-mail worms use e-mail as a way of
replicating themselves into vulnerable
computers.
Task 1
Show whether the followings statements
are true or false (T/F).
1. Conventional mail is another name for email.
2. Electronic mail is human communication
method based on text.
3. The post office is like a mail server to an email.
4. A traditional mail is often called snail mail by
computer users.
5. The “Subject” field indicates the recipient of the
mail.
6. Email Bomb means sending a very big
volume of emails.
7. A subject line identifies the sender.
8. Phishing is a technique used to gain
personal information for purposes of
identity theft, using fraudulent e-mail
messages.
Further readings
• http://depts.alverno.edu/cil/mod2/whatisem
ail.html
• http://en.wikipedia.org/wiki/E-mail
• http://dragon.ep.usm.edu/~it365/module/B
asics/Basics.htm
Send the answer via sms to 8181
Choose a, b, c, or d for the correct answer.
1. The conventional mail is called ….
a. email c. snail mail
b. snake mail d. blackmail
2. An email message made up of ….
a. server c. message body
b. header d. signature
3. Commercial offers sent to our email
without our request is called ….
a. phishing c. worm
b. spam d. bomb
4. In message header, “To” is for the ….
a. recipient’s address c. topic
b. sender’s address d. time
5. It uses e-mail to duplicate themselves
into vulnerable computers.
a. email bomb c. spam
b. phishing d. email worm
Meeting 14
a. Website
A website is a site (location) contains a
collection of pages on the World Wide
Web. Each Web site contains a home
page, which is the first document users
see when they enter the site.
Home page, as the name suggests, is
the main or opening page of a website.
You will notice that several websites use
the word "Home" or an image of a house
to guide surfers back to the main page.
The URL or Uniform Resource Locator
is the specific address of a webpage, like
http://geocities.com/toe6000/www1.html
The site might also contain additional
documents and files. Each site is owned
and managed by an individual, company
or organization.
Web page is a document written in
Hypertext Mark-up Language (HTML)
code that contains text and links to other
pages, files, or parts of the document. The
earliest Web pages were all-text
documents and at present there are still
text-based browsers like Lynx. Although
Tim Berners-Lee also wrote the first
multimedia browser in 1990, graphical
user-interface (GUI), browsers didn't
become popular until Mosaic came along
in 1993.
Task 1
Is it true or false (T/F)?
1. Each Web site contain a house page.
2. Tim Berners-Lee also wrote the first
multimedia browser in 1991.
3. Home page, as the name suggests, is
the main or opening page of a website.
4. No one owns and manages each site in
the Internet.
5. Mosaic is one of internet browsers.
b. Search engine
Search Engine is a program that
searches documents for specified
keywords and returns a list of the
documents where the keywords were
found. Although search engine is really a
general class of programs, the term is
often used to specifically describe systems
like Google, Alta Vista and Excite that
enable users to search for documents on
the World Wide Web and USENET
newsgroups.
In a simpler way, a Web search
engine is a tool designed to search for
information on the World Wide Web.
Information may consist of web pages,
images, information and other types of
files. Search engines operate
algorithmically or are a mixture of
algorithmic and human input.
There are basically three types of
search engines: Those that are powered
by robots (called crawlers; ants or spiders)
and those that are powered by human
submissions; and those that are a hybrid
of the two.
The following description explains how
Crawler-based search engines works.
Typically, a search engine works by
sending out a spider to fetch as many
documents as possible. Another program,
called an indexer, then reads these
documents and creates an index based on
the words contained in each document.
Each search engine uses a proprietary
algorithm to create its indices such that,
ideally, only meaningful results are
returned for each query.
Did You Know...
The first tool for searching the Internet,
created in 1990, was called "Archie". It
downloaded directory listings of all files located
on public anonymous FTP servers; creating a
searchable database of filenames. A year later
"Gopher" was created. It indexed plain text
documents. "Veronica" and "Jughead" came
along to search Gopher's index systems. The
first actual Web search engine was developed
by Matthew Gray in 1993 and was called
"Wandex".
Examples of three search engines
Task 2
Check your understanding.
1. How many tools to search the Internet ever
created from 1990-1993? Name them.
2. How do surfers back to the main page?
3. What is website?
4. What is search engine?
5. Mention types of search engines.
Further readings:
• http://dragon.ep.usm.edu/~it365/module/In
ternet/Internet.htm
• http://www.webopedia.com/DidYouKnow/I
nternet/2003/HowWebSearchEnginesWor
k.asp
• http://www.webopedia.com/quick_ref/Inter
net_Search_Engines.asp
Task 3
Google Search Tips:
a. You can search for a phrase by using quotations
["like this"] or with a minus sign between words [likethis].
b. You can search by a date range by using two dots
between the years [2004..2007].
c. When searching with a question mark [?] at the end
of your phrase, you will see sponsored Google
Answer links, as well as definitions if available.
In groups translate the
following!
d. Google searches are not case sensitive.
e. By default Google will return results which include
all of your search terms.
f. Google automatically searches for variations of your
term, with variants of the term shown in yellow
highlight.
g. Google lets you enter up to 32 words per search
query.
Send answer via sms 8181
Choose a, b, c, or d for the correct answer.
1. The first actual Web search engine was
developed by Matthew Gray in 1993 and
was called ….
a. spandex c. wantex
b. wandex d. windex
2. Search engines powered by robots are
called ….
a. creepy crawlers c. bugs
b. aunts d. spiders
3. At present there are still text-based
browsers like ….
a. Lynx c. sync
b. spynx d. none of the above
4. The following are search engines, except ….
a. Win Vista c. Google
b. MSN d. Excite
5. What does URL stand for?
a. Uniform Resource Location
b. United Resource Local
c. United Resource Locator
d. Uniform Resource Locator