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LESSON 1

I NTRODUCTI ON TO I NFORMATI ON AND COMMUNI CATI ON TECHNOLOGY ( I CT)

EVOLUTI ON OF COMMUNI CATI ON

WHAT I S I CT?

ICT is the technology required for information processing, in particular, the use of electroniccomputers, communication devices and software applications to convert, store, protect,process, transmit and retrieve information from anywhere, anytime.

I NFORMATI ON

Information refers to the knowledge obtained from reading, investigation, study or

research.

We need information to make decisions and to predict the future. For example, scientistscan detect the information of a tsunami using the latest technology and warn the public toavoid disasters in the affected areas.

COMMUNI CATI ON

Communication is an act of transmitting messages. It is a process whereby information isexchanged between individuals using symbols, signs or verbal interactions.

TECHNOLOGY

Technology is the use of scientific knowledge, experience and resources to create processes

and products that fulfill human needs. Technology is vital in communication.

A id ing Com m un ica t i on

Telephone and fax machines are the devices used in extending communication.

Sp r e a d in g I n f o r m a t i o n

To broadcast information such as news or weather reports effectively. Radio, television,satellites and the World Wide Web (www) are powerful tools that can be used.

LESSON 2EVOLUTI ON OF COMPUTERS

FI RST GENERATI ON (1 940 -19 56)

The first generation of computer were huge, slow, expensive and often unreliable. In 1946,two Americans, Presper Eckert and Willian Mauchly build the ENI AC (Electronic NumericalIntegrator and Computer). It use v a cu u m t u b e instead of mechanical switches of the

MARK In 1951, Eckert and Mauchly build the UNIVAC, which could calculate at the rate of10,000 addition per seconds.

SECOND GENERATI ON (1 95 6- 19 63 )

The famous computer scientists during the second generation era were:The creation oft rans i s to r spark the production of a wave of second generation computer.Transistor was small devices use to transfer electronic signals across a resister. Transistors

had many advantages compared to other hardware technology.


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THI RD GENERATI ON ( 196 4- 197 1)

In the third generation era, the IBM 370 series were introduced in 1964. It came in severalmodels and sizes.It was used for business and scientific programs. Other computer modelsintroduced were CDC 7600 and B 2 5 0 0 .

The development of integrated circuit (IC), signal the beginning of the third generationcomputers. Sil i cone ch ip s were manufactured in 1961 at the Silicone Valley. Then camethe integrated circuit technology, which had reduced the size and cost of computers.

It is a complete electronic circuit on a small chip of silicone. Which is also known as s e m iconduc to r . Other than that, the Magnetic Core Memory was replaced by a device called themicrochip. Also the first 256 bit RAM was introduced and it was the basis for development of

1K bit RAM.

FOURTH GENERATI ON ( 19 71 -PRESENT)

It took only 55 years for the 4 generations to evolve. The growth of the computer industry

developed technologies of computer inventions. There are many types of computer modelssuch as:

Apple Macintosh

IBM

DELL

ACER

In 1971 Intel created the first mic rop rocessor . In 1976, Steve Jobs built the first Applecomputer. Then, in 1981, IBM introduced its first personal computer.

During the fourth generation, hardware technology such as silicone chips, microprocessorand storage devices were invented. A microprocessor is a specialized chip which is

developed for computer memory and logic.

FI FTH GENERATI ON ( PRESENT & BEYOND)

The fifth generation computers are technologically advance and are still being development

to become more efficient. The inventions of new hardware technology in the fifth generationhave grown rapidly including many other modern computer devices such as :

silicone chips

processor

robotics

virtual reality

intelligent systems programs which translate languages

NEW ERA COMPUTER

After the fifth generation computer, the technology of computer has become moreadvanced, modern and sophisticated. The latest invention in the era of computers are :

Super Computers

Mainframe Computers

Mini Computers

Personal Computers

Mobile Computers

In the new era of computers, expert system such as teleconferencing and speech-recognition system have been invented as part of modern world communication tools.


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LESSON 3

USAGE OF I CT I N DAI LY LI FE

EDUCATI ONToday, most schools and higher educational institutions have computers in the classroomfor teacher and students. In education, teachers, students, researchers and school

administrators benefits from the usage of ICT.

BANKI NGThe computer is the nerve centre of the banking system around the world. It functions to

control the entire banking system that also includes 'Electronic Banking Services'.Electronic banking provides 24 hour services. The services include :

Automated Teller Machine (ATM)

Cheque Deposit Electronic Fund Tranfer

Direct Deposit

Pay by phone system

Personal computer banking/ internet banking

I NDUSTRY

Computers are used to facilitate production planning and control systems, to support chainmanagement and to help in product design in the industrial sector.In the industrial sectorworkers, researchers and administrator benefits from the usage of ICT.

E-COMMERCE

E-commerce helps in boosting the economy. It makes buying and selling activities easier,more efficient and faster. For this application, computers, Internet and shared software areneeded.

LESSON 4COMPUTERI SED AND NON- COMPUTERI SED SYSTEMS

COMPUTER SYSTEM

A computer system consists of a set of hardware and software which processes data in ameaningful way.

ED UCA TI O N W I T H I CT

education is the science of teaching and learning of specific skills

it also imparts knowledge, good judgement and wisdom

BANKI NG SYSTEM WI TH I CT

all transactions are done by computers

transaction can be done at anytime and place

online services, phone banking system, credit cards are available

I NDUSTRY WI TH I CT

Computers and telecommunications industry became very opular and profitable sinceproduction can be increased through an all day operation.

COMMERCE W I TH I CT

E-commerce plays an important role in the economic scene. It includes distribution, buying,selling and servicing products that are done electronically.


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LESSON 5

THE I MPACT OF I CT ON SOCI ETY

FASTER COMMU NI CATI ON SPEED

In the past, it took a long time for any news or messages to be send. Now with the

Internet, news or messages are sent via e-mail to friends, business partners or to anyoneefficiently. With the capability of bandwidth, broadband and connection speed on theInternet, any information can travel fast and at an instant. It saves time and is inexpensive.

LOWER COMMUNI CATI ON COST

Using the Internet is cost-effective than the other modes of communication such astelephone, mailing or courier service. It allows people to have access to large amounts of

data at a very low cost. With the Internet we do not have to pay for any basic servicesprovided by the Internet. Furthermore, the cost of connection to the Internet is relativelycheap.

RELI ABLE MODE OF COMMUNI CATI ON

Computers are reliable. With the internet, information could be accessed and retrieved fromanywhere and at anytime. This makes it a reliable mode of communication. However, the

input to the computer is contributed by humans. If the data passed to the computer isfaulty, the result will be faulty as well. This is related to the term GIGO.

GIGO is a short form for Garbage In Garbage Out. It refers to the quality of outputproduced according to the input. Normally bad input produces bad output.

EFFECTI VE SHARI NG OF I NFORMATI ON

With the advancement of ICT, information can be shared by people all around the world.People can share and exchange opinions, news and information through discussion groups,mailing list and forums on the Internet. This enable knowledge sharing which will

contribute to the development of knowledge based society.

PAPERLESS ENVI RONMENTICT technology has created the term paperless environment. This term means informationcan be stored and retrieved through the digital medium instead of paper. Online

communication via emails, online chat and instant messaging also helps in creating thepaperless environment.

BORDERLESS COMM UNI CATI ON

Internet offers fast information retrieval, interactivity, accessibility and versatility. It hasbecome a borderless sources for services and information. Through the Internet,information and communication can be borderless.

SOCI AL PROBLEMS

There are some negative effects of ICT. It has created social problems in the society.Nowadays, people tend to choose online communication rather than having real time

conversations. People tend to become more individualistic and introvert.Another negative effect of ICT is :

fraud

identity theft

Pornography

HackingThis will result a moral decedent and generate threads to the society.

HEALTH PROBLEMS

A computer may harm users if they use it for long hours frequently. Computer users arealso exposed to bad posture, eyestrain, physical and mental stress. In order to solve thehealth problems, an ergonomic environment can be introduced. For example, an ergonomicchair can reduces back strain and a screen filter is used to minimize eye strain.


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LESSON 6

COMPUT ER ETHI CS

ETHI CS I N GENERALA guideline is needed to stop the current technology products from being exploited forexample replicating original CDs and selling them as pirated software, this unethical

behaviour can be controlled by the code of conducts.

GUI DELI NES ON THE E-M AI L AND I NTERNET USAGESome guidelines from the Department of Public Services of Malaysia:

use only individual e-mail address to forward individual opinion

keep the identity name and password a secret to avoid the misuse of your e-

mail without your knowledge e-mail must be active to promptly reply the necessary actions needed for any

matters

ensure the total mail kept in the box is within the computer storage capacity

scan files regularly to avoid the transmission of virus from one computer to

another do not send e-mails that contain classified information which can be used to

tarnish other people or country

choose a suitable time to search the Internet to save access time and cost

beware of prohibited sites which could affect one's moral, organisation ornation

UNETHI CAL COMPU TER CODE OF COND UCTS

With the advancement of ICT, it is easy for anyone to retrieve your information from theInternet. You may not realise that when you fill a form on the Internet, your informationmay be exposed and stolen. Examples of unethical computer code of conducts include:

modifying certain information on the Internet, affecting the accuracy of the

information selling information to other parties without the owners permission

using information without authorization involvement in stealing software

invasion of privacy

ETHI CAL COMPUT ER CODE OF COND UCTS

Examples of ethical computer code of conducts include:

sending warning about viruses to other computer users

asking permission before sending any business advertisements to others

using information with authorization

LESSON 7

THE DI FFERENCES BETWEEN ETHI CS AND LAW

DEFI NI TI ON OF ETHI CS

In general, ethics is a moral philosophy where a person makes a specific moral choice andsticks to it. On the other hand, ethics in computing means moral guidelines to refer to when

using the computer and computer networks. This includes the Internet.

DEFI NI TI ON OF LAW

Law is a legal system comprising of rules and principles that govern the affairs of acommunity and controlled by a political authority.

WH Y DO WE NEED ETHI CS AND LAW I N COMPUTI NG?

Respecting Ownership Respecting Privacy

Respecting Property


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SI MI LARI TI ES BETWEEN ETHI CS AND LAW

Both ethics and law are complimentary to each other and are made:

to guide user from misusing computers

to create a healthy computer society, so that computers are used tocontribute to a better life

to prevent any crime

DI FFERENCES BETW EEN ETHI CS AND LAW S

ETHI CS

GUIDELINE As a guideline to computer users.

MORAL STANDARDS Ethical behaviour is judged by moral

standards.

FREE TO FOLLOW Computer users are free to follow or ignorethe code of ethics.

NO PUNISHMENTS No punishment for anyone whoviolates ethics.

UNIVERSALS Universal, can be applied anywhere,all over the world.

PRODUCE ETHICAL COMPUTER USERS To produce ethical computer users.IMMORAL Not honouring computer ethics means

ignoring the moral elements (immoral).

LAW

CONTROL As a rule to control computer users.

JUDICIAL STANDARDS Law is judged by judicial standards.

MUST FOLLOW Computer users must follow the regulationsand law.

PENALTIES, IMPRISONMENTSAND OTHER PUNISHMENTS

Penalties, imprisonments and otherpunishments for those who break the law.

DEPENDS ON COUNTRY Depends on country and state wherethe crime is committed.

PREVENT MISUSING OF COMPUTERS To prevent misuse of computers.

CRIME Not honouring the law meanscommitting a crime.

UNETHI CAL VS. LAW BREAKI NG CONDUCTS

Unethical:

using the office computer to do personal things

reading your friends e-mail without his or her permission plagiarising and using materials from the Internet for your class assignment

without giving credit to the original author.Law breaking:

sending a computer virus via e-mail hacking into your schools database to change your examination results. selling pirated software in a night market

LESSON 8

I NTELLECTUAL PROPERTY RI GHTS

DEFI NI TI ON OF I NTELLECTUAL PROPERTY

Intellectual Property refers to works created by inventors, authors and artists. These worksare unique and have value in the market place. All protected by a group of legal rights.

I NTELLECTUAL PROPERTY LAWIntellectual Property laws cover ideas, inventions, literary creations, unique names,

business models, industrial processes, computer program codes and more.


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I NVENTI ONS PROTECTED BY I NTELLECTUAL PROPERTY LAWS

As businesses continue to expand globally, business owners must realise the importance of

getting professional advice on how to establish and safeguard their intellectual propertyrights. These include :

Trademarks

Service marks

Trade/company names Copyrights

Patents

I NTELLECTUAL PROPERTY PROTECTI ON

There are four types of Intellectual Property protection. They are patents for invention,trademarks for brand identity, designs for product appearance and copyright for material.

Patents for inventions Trademarks for brand identity

Design for product appearance

Copyright for material

Paten t s fo r i nven t i onsUtility, design or plant patents that protect inventions and improvements to existing

inventions

T r ad e m a r k s f o r b r a n d i d e n t i t y

Words, names, symbols, devices and images that represent products, goods or services.

Design fo r p roduc t app earance

Literary and artistic material, music, films, sound recordings and roadcasts, includingsoftware and multimedia.

Copy r i gh t f o r ma t e r i a l

The features of, in particular,the lines, contours, colours,shape, texture or material of theproduct itself or its ornamentation.

LESSON 9

PRI VACY I N COMPUTER USAGE

WH AT I S PRI VACY?

Privacy in IT refers to data and information privacy.

Data refers to a collection of raw unprocessed facts, figures and symbols. Then, computeris used to process data into information. In general, data include texts, numbers, sounds,

images and video.

I n f o r m a t i o n privacy is described as the rights of individuals and companies to deny orrestrict the collection and use of information about them.

W AYS COMPU TER TECHN OLOGY THREATEN OUR PRI VACYEvery time you click on an advertisement or register a software product online, your

information is entered into a database. Computer technology can also threaten privacythrough spam. Do you know what spam is? Spam is unsolicited e-mail messages,advertisements or newsgroup postings sent to many recipients at once.

How does computer technology threaten the privacy of our data?It is done through:

Cookies Electronic profile

Spyware


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Cookies

are used to identify users by web casting, e-commerce and other web applications

contain user information and are saved in the computer hard disk

are used by some websites to store passwords and track how regularly we visit awebsite, thats how we become potential targets for web advertisers

enable web sites to collect information about your online activities and store them

for future use, then the collected details will be sold to any company that requestsfor it.

Elec t ron ic pro f i le

electronic profile is the combining of data in a database that can be sold to theInternet by the company to the interested parties.

this database is in a form such as magazine subscription or product warranty cards

that had been filled by online subscribers. the information in electronic profile includes personal details such as your age,

address and marital status.

Sp y w a r e

refers to a program that collects user information without the users knowledge. can enter computers, sneaking in like a virus.

is a result of installing new programs.

communicates information it collects to some outside source while we are online.

W HY DO W E NEED PRI VACY?

We need privacy for anonymity. For example, the Internet creates an elaborate trail of datadetailing a person surfing on the Web because all information is stored inside cookies. Wedo not want our trail to be detected. We also need privacy for confidentiality. We do notwant our private lives and habits exposed to third parties.

CAN PRI VACY BE PROTECTED?

Privacy can be protected by:

( a ) P r i vacy l awThe privacy laws in Malaysia emphasises on the following:

Security Services to review the security policy

Security Management to protect the resources

Security Mechanism to implement the required security services

Security Objects, the important entities within the system environment

( b ) U t i li t i e s s of t w a r e

Example: anti-spam program, firewall, anti-spyware and antivirus.

LESSON 10

AUTHENTI CATI ONS

Authentication is a process where users ve r i f y that they are who they say they are. Theuser who attempts to perform functions in a system is in fact the user who is authorised to

do so.

For Example : When you use an ATM card, the machine will verify the validation of the cardthen the machine will request for a pin number. This is where the authentication processtakes place.


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AUTHENTI CATI ON

METHODS OF AUTHENTI CATI ON

There are two commonly used authentication methods, which are biometric device andcallback system.

Bi om e t r i c d e v ic e is a device that translates personal characteristics into a digital code thatis compared with a digital code stored in the database.

Cal lback sys tem refers to the checking system that authenticates the user.

BI OMETRI C DEVI CES

Fingerp r i n t Recogn i t i onIn order to prevent fake fingers from being used, many biometrics fingerprint systems alsomeasure blood flow, or check for correctly arrayed ridges at the edges of the fingers.

Fac ia l Recogni t io n

Facial recognition analyses the characteristics of an individual's face images capturedthrough a digital video camera.

Hand Geom et ry Scann ing

Hand scanning involves the measurement and analysis of the shape of one's hand.

I r i s Scann ing

Iris scanning analyses the features that exist in the coloured tissues surrounding the pupilwhich has more than 200 points that can be used for comparison, including rings, furrowsand freckles.

Ret in a l Scann in g

Retinal biometrics involves the scanning of retina and analysing the layer of blood vessels atthe back of the eye.

Vo ic e Re co g n it i o n

Voice recognition system compares a persons live speech with their stored voice pattern.

Signa tu re Ver i f i ca t i on Sys tem

Signature verification system uses special pen and tablet. After pre-processing thesignature, several features are extracted.

CALLBACK SYSTEM

The callback system is commonly used in the bank operation and business transaction.

WH Y I S AUTHENTI CATI ON I MPORTANT?

Authentication is important in order to safeguard against the unauthorised access and use.


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LESSON 11

VERI FI CATI ONS

VERI FI CATI ONVerification is the act ofprov ing o r d i sp rov ing t he co r rec tness o f a system with respectto a certain formal specification.

METHODS OF VERI FI CATI ON

There are two methods commonly used in verification, which are user identification andprocessed object.

User i den t i f i ca t i on refers to the process of validating the user.

Processed ob j ec t refers to something the user has such as identification card, securitytoken and cell phone.

USER I DENTI FI CATI ON

The examples of validating process using the user identification are:

Key in the user name to log-in to a system and the system will verify whether theuser is valid or invalid user

Show the exam slip to verify that you are the valid candidate for the exam.

show a passport before departure.

LESSON 12

CONTROVERSI AL CONTENT

CONTROVERSI AL CONTENT

A controversial content is information that causes disagreement in opinions and may causethe disruption of peace because different people or culture will have different views

I SSUES ON CONTROVERSI AL CONTENTSThe issues on controversial contents are always focusing on pornography and slander.Malaysia considers pornography and slander as illegal.

Pornography Creative activity (writing or pictures or films etc.) of no literary or artistic value

other than to stimulate sexual desire.

Slander Oral comm unication of false statement s injurious to a person's reputation.A false and m alicious stat ement or report about someone.

DEFI NI TI ON OF PORNOGRAPHY

The definition of pornography is any form of media or material (like books or photographs)

that depicts erotic behaviour and is intended to cause sexual excitement.

Pornography tends to exploit men, women and children in a distasteful manner.

SLANDER

Slander is another example of controversial content.

Slander is a legal term for false and malicious statement (meaning knowing that it is false,or reckless disregard that it was false) about someone.

Exam ples :

You wrote an e-mail that a fellow classmate was having an affair with a teacher, eventhough it was not true. You then sent it to five other friends.


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I MPACTS ON MALAYSI AN SOCI ETY

Pornography

can lead to criminal acts such as exploitation of women and children can lead to sexual addiction or perversion

can develop low moral value towards other men, women or children

can erode good religious, cultural and social beliefs and behaviour

Slander can develop into a society that disregards honesty and truth

can develop bad habit of spreading untruths and rumours

can lead to unnecessary argument

can cause people to have negative attitudes towards another person

LESSON 13

THE PROCESS OF I NTERNET FI LTERI NG

I NTERNET FI LTERI NG

It is our responsibility to ensure that the teenagers are protected from these corruptions ofthe mind by filtering access to the Internet.Internet filtering is a process that prevents or

blocks access to certain materials on the Internet.

It is our responsibility to ensure that the teenagers are protected from these corruptions ofthe mind by filtering access to the Internet.

W h a t i s I n t e r n e t f i l t e r i n g ?

Internet filtering is a process that prevents or blocks access to certain materials on theInternet. Filtering is most commonly used to prevent children from accessing inappropriatematerial and to keep employees productive on the Internet.

CONTROLLI NG ACCESS TO THE I NTERNETThe current preferred method of choice to limit access on the Internet is to filter contenteither by:

keyword blocking

site blocking

web rating systems

These methods require software to be installed at a client of server level.

KEYWORD BLOCKI NG

One of the strategies is by using the keyword blocking method. This method uses a list ofbanned words or objectionable terms.

As the page is downloading, the filter searches for any of these words. If found, it will blockthe page completely, stop downloading the page, block the banned words and even shutdown the browser.

SI TE BLOCKI NG

software company maintains a list of dubious Internet sites

the software prevents access to any sites on this list

denial lists regularly updated

some software provides control over what categories of information you block

Who decides what goes on the denial list and what criteria are they using?

can you keep track of the whole of the Internet?

filters can use both site blocking and word blocking


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W EB RATI NG SYSTEMS

Web sites are rated in terms of nudity, sex, violence and language. The Recreational

Software Advisory Council (RSACI) is responsible for the rating of the websites on thecontent on the internet.

ratings done either by the web page author or by the independent bureau.

browsers set to only accept pages with certain levels of ratings.

LESSON 14CYBER LAW

What i s Cyber Law ?

Cyber law refers to any laws relating to protecting the Internet and other online

communication technologies.

NEEDS FOR CYBER LAW

These concerns and issues clearly indicate why cyber laws are needed in online activities.

THE CYBER LAW ACTS I N MA LAYSI AThe Malaysian Government has already passed several cyber laws to control and reduce theInternet abuse. These cyber laws include:

Digital Signature Act 1997

Computer Crimes Act 1997

Telemedicine Act 1997

Communications and Multimedia Act 1998

DI GI TAL SI GNATURE ACT 199 7

The Digital Signature Act 1997 secures electronic communications especially on the

Internet. Digital Signature is an identity verification standard that uses encryptiontechniques to protect against e-mail forgery. The encrypted code consists of the usersname and a hash of all the parts of the message.

COMPUTER CRI MES ACT 19 9 7

The Computer Crimes Act 1997 gives protection against the misuses of computers andcomputer criminal activities such as unauthorised use of programmes, illegal transmission

of data or messages over computers and hacking and cracking of computer systems andnetworks. By implementing the Computer Crimes Act 1997, users can protect their rights toprivacy and build trust in the computer system. At the same time, the government can havecontrol at a certain level over cyberspace to reduce cyber crime activities.

TELEMEDI CI NE ACT 19 97

The Telemedicine Act 1997 ensures that only qualified medical practitioners can practicetelemedicine and that their patient's rights and interests are protected.

These act provides the future development and delivery of healthcare in Malaysia.

CYBER LAW

Integrity and Securityof Information

Legal Status of Online

Transactions

Privacy and Confidentially

of Information

Security ofGovernment Data

Intellectual Property

Rights


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COMMUNI CATI ONS AND MULTI MEDI A ACT 199 8

The implementation of Communication and Telecommunication Act 1998 ensures that

information is secure, the network is reliable and the service is affordable all over Malaysia.

This Act also ensures high level of user's confidence in the information and communicationtechnology industry.

LESSON 15COMPUT ER CRI MES

COMPUT ER CRI MES

A computer crime is defined as any criminal activity that is related to the use of computers.

These activities include computer fraud, copyright infringement, computer theft andcomputer attack.

COMPUT ER FRAUD

Computer fraud is defined as having an intention to take advantage over or causing loss to

other people, mainly on monetary basis through the use of computers.

COPYRI GHT I NFRI NGEMENT

Copyright infringement is defined as a violation of the rights secured by a copyright.Copyright infringement involves illegal copy or reproduction of copyrights material by theblack market group. The open commercial sale of pirated item is also illegal.

COMPUTER THEFT

Computer theft is defined as the unauthorised use of another persons property with theintention to deny the owner the rightful possession of that property or its use.Examples of computer theft include:

transfer of payments to the wrong accounts

tap into data transmission lines on database at no cost divert goods to the wrong destination

COMPUT ER ATTA CK

Computer attack may be defined as any activities taken to disrupt the equipment of

computer systems, change processing control or corrupt stored data.Computer attack can be in the forms of:

physical attack that disrupt the computer facility or its transmission lines.

an electronic attack that uses the power of electromagnetic energy tooverload computer circuitry.

a computer network attack that uses a malicious code to exploit a weaknessin software, or in the computer security practices of a computer user

LESSON 16

COMPUT ER SECURI TY

DEFI NI TI ON OF COMPUTER SECURI TYComputer security means protecting our computer systems and the information they

contain against unwanted access, damage, destruction or modification.

We need to protect our computer from any intruders such as hackers, crackers and scriptkiddie.

We do not want strangers to read our e-mail, use our computer to

attack other systems, send forged e-mail from our computer, or examine personalinformation stored on our computer such as financial statements.


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TYPES OF COMPUTER SECURI TY

Three types of computer security are:

a) hardware securityb) software security/data securityc) network security

a) HARDW ARE SECURI TYHardware security refers to security measures used to protect the hardware specifically thecomputer and its related documents.

The examples of security measures used to protect the hardware include PC-locks,keyboard-locks, smart cards and biometric devices.

b) SOFTWARE AND DATA SECURI TYSoftware and data security refers to the security measures used to protect the software andthe loss of data files.

Examples of security measures used to protect the software are activation code and serial

number.

c) NETW ORK SECURI TY

The transfer of data through network has become a common practice and the need toimplement network security has become significant.

PERSONAL COMPUTER SECURI TY CHECKLI ST

In order to make sure our computers are secured, here are the computersecurity checklist to follow.

Do not eat, drink or smoke near the computer

Do not place the computer near open windows or doors

Do not subject the computer to extreme temperatures

Clean the equipment regularly Place a cable lock on the computer Use a surge protector Store disks properly in a locked container

Maintain backup copies of all files

Stores copies of critical files off sites Scan a floppy disk before you open it Do not open any unknown email received

LESSON 17

I NTRODUCTI ON COMPUTER THREATS

The computer is a great tool to store important information. In certain cases, theinformation is very vital that losing it will harm the computer system.

Computer threats can come from many ways either from human or natural disasters. Forexample, when someone is stealing your account information from a trusted bank, thisthreat is considered as a human threat. However, when your computer is soaked in heavy

rain, then that is a natural disaster threat.

MALI CI OUS CODE

Malicious code is also known as a rogue program. It is a threat to computing assets bycausing undesired effects in the programmers part. The effect is caused by an agent, withthe intention to cause damage.

The agent for malicious code is the writer of the code, or any person who causes itsdistribution. There are various kinds of malicious code. They include virus, Trojan horse,logic door, trapdoor and backdoor, worm and many others.


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a) V I RUS

a program that can pass on the malicious code to other programs by

modifying them

attaches itself to the program, usually files with .doc, .xls and .exe extensions destroys or co-exists with the program

can overtake the entire computing system and spread to other systems

b) TROJAN HORSE

a program which can perform useful and unexpected action must be installed by users or intruders before it can affect the systems

assets

an example of a Trojan horse is the login script that requests for users loginID and password

the information is then used for malicious purposes

c) LOGI C BOMB

logic bomb is a malicious code that goes off when a specific condition occurs.

an example of a logic bomb is the time bomb

it goes off and causes threats at a specified time or date

e) TRAPDOOR OR BACKDOOR

a feature in a program that allows someone to access the program withspecial privileges

f ) WORM

a program that copies and spreads itself through a network

Pr im ary D i f f e rences Be tw een Worm s And v i ru ses

HACKER

Hacking is a source of threat to security in computer. It is defined as unauthorised access tothe computer system by a hacker. Hackers are persons who l ea rn about the computersystem i n de ta i l. They write program referred to as hacks. Hackers may use a modem orcable to hack the targeted computers.

NATURAL AND ENVI RONMENTAL THREATS

Computers are also threatened by natural or environmental disaster. Be it at home, stores,offices and also automobiles.Examples of natural and environmental disasters: Flood Fire Earthquakes, storms and tornados

Excessive Heat Inadequate Power Supply

THEFT

Two types of computer theft:1) Computer is used to steal money, goods, information and resources.2) Stealing of computer, especially notebook and PDAs.

Three approaches to prevent theft:1) prevent access by using locks, smart-card or password2) prevent portability by restricting the hardware from being moved

3) detect and guard all exits and record any hardware transported

W or m Vi r u s

Operates through the network Spreads through any mediumSpreads copies of itself as a standaloneprogram

Spreads copies of itself as a programthat attaches to otherprograms


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LESSON 18

SECURI TY MEASURES

Security measures mean the precautionary measures taken toward possible danger ordamage. There are 6 type of security measures.

1) DATA BACKUPData Backup is a program of file duplication. Backups of data applications are necessary sothat they can be recovered in case of an emergency.

2) CRYPTOGRAPHY

Cryptography is a process ofh i d i n g i n f o r m a t i o n by altering the actual information intodifferent representation, for example, an APA can be written as I? X.

Almost all cryptosystems depend on a key such as a password like the numbers or a phrasethat can be used to encrypt or decrypt a message.

The traditional type of cryptosystem used on a computer network is called a symmetric

secret key system.

3 ) A NT I V I RU S

An antivirus program protects a computer against viruses by identifying and removing anycomputer viruses found in the computer memory, on storage media or incoming e-mailfiles. An antivirus program scans for programs that attempt to modify the boot program,the operating system and other programs that normally are read from but not modified.

I DENTI FYI NG VI RUS

Two technique are used to identify the virus.

If an antivirus program identifies an infected file, it attempts to remove its virus, worm or

Trojan horse. If the antivirus program cannot remove the infection, it often quarantines theinfected file. Quarantine is a separate area of a hard disk that holds the infected file untilthe infection can be removed. This step ensures other files will not become infected. Patentsfor inventions Utility, design or plant patents that protect inventions and improvements toexisting inventions

4) ANTI -SPYWARE

Spyware is a program placed on a computer without the users knowledge. It secretlycollects information about the user.

The spyware program communicates information to the outside source.

An anti-spyware application program sometime called tracking software or a spybot is usedto remove spyware.

Among of the popular anti-spyware programs are:

Spybot Search and Destroy Ad-aware Spyware Blaster

5) FI REW ALL

Firewall is a piece of hardware or software which functions in a networked environment toprevent some communications forbidden by the security policy.

Firewall implement a security policy. It might permit limited access from in or outside the

network perimeters or from certain user or for certain activities.


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6) HUM AN ASPECTS OF SECURI TY MEASURES

Human aspects refer to the user and also the intruder of a computer system.

It is one of the hardest aspects to give protection to.

The most common problem is the lack of achieving a good information security procedure.

LESSON 19

RELATI ONSHI P BETW EEN SECURI TY THREATS AND SECURI TY MEASURES

SECURI TY TH READS

Secur i t y t h r ea ts may come from in many forms. For example, when someone is invadingyour account information from a trusted bank, this act is considered as a security threat.

Secur i t y m easures can be used to prevent this invader from getting the accountinformation. For example, the bank can use a firewall to preventunauthorised access to its database.

MALI CI OUS CODE THREATS VS. ANTI VI RUS AND AN TI -SPYW ARE

Security threats include virus, Trojan horse, logic bomb, trapdoor and backdoor, and worm.

Antivirus and anti-spyware can be used to protect the computer from the threats by: limiting connectivity

allowing only authorised media for loading data and software enforcing mandatory access controls

blocking the virus from the computer program

HACKI NG VS. FI REW ALL

Hacking is an unauthorised access to the computer system done by a hacker. We can usefirewall or cryptography to prevent the hacker from accessing our computers.

A firewall permits limited access to unauthorised users or any activities from the network

environment. Cryptography is a process of hiding information by changing the actualinformation into different representation, for example, an APA can be written as 7&*.


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DETECTI NG I LLEGAL ACCESS TO SYSTEMS

The computer system is able to detect any illegal access to the system by a user who does

not have any authorisation. Basically, a corporation will simply use tcpwrappers and tripwireto detect any illegal access to their system. User's access will be reviewed periodically bycomputer operations. On going internal audits will be made to ensure detection of violationsof security and unauthorised modifications to software and data .

TCPWRAPPERS

Tcpwrappers stop the attempted connection

examines its configuration files

will decide whether to accept or reject the request.

Tcpwrappers will control access at the application level, rather than at the socket level like

iptables and ipchains. The system will run tcpwrappers to log access to ftp, tftp, rch, rlogin,rexec and telnet.

TRI PWI RE

Tripwire will detect and report on any changes in the thousands of strategic system files.The system will run tripwire to determine if system files have changed.

PREVENTI NG I LLEGAL ACCESS TO SYSTEMS

Ways to prevent illegal access to systems:1. Run anlpassword to make password cracking difficult.2. Run tcpwrappers to check if the name for an ip address can be provided by DNC3. Use a callback system to prevent unauthorised use of stolen passwords.

PREVENTI NG I LLEGAL ROOT ACCESS

Sudo stands for (Superuser do) and is a program in Unix, Linux and similar operatingsystems such as Mac OS X that allows users to run programs in the form of another user

(normally in the form of the system's superuser).

Sudo allows a permitted user to execute a command as the superuser or another user, asspecified in the sudoers file.

PATCH

Patch supplies small updates to software, provided that the source code is available.

Patch is a name of an UNIX utility. It applies a script generated by the different program toa set of files that allows changes from one file to be directly applied to another file.

Resources are not enough to patch all security holes that we hear about through the

bugtraq list.

LESSON 21

COMPUTER APPLI CATI ONS I N THE SOCI ETY

The computer has change the society today as much as industrial revolution changedsociety in 18th and 19th century. People interacts directly with computer in education,finance, government, health care, science, publishing, tourism, and industry.

Computers help them to do their work faster and more efficient by using the softwareapplication that consist of special program for specific task.


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SOFTWARE APPLI CATI ONS

Software applications are used for many reasons. Such as to enhance the learning process,

to help in business activities, to assist the graphics and multimedia project and to fasilitatecommunication.

Ar ea Ex am p les o f so f t w ar e ap p l i cat ion s

Home andEducation

Integrated software, Personal finance, Legal, Tax Preparation,Clip Art/Image Gallery, Home Design/Landscaping and

Reference

Business Word Processing, Spreadsheet, Database, PresentationGraphics, Personal Information Manager, Software Suite,

Project Management and Accounting

Graphicsand Multimedia

Computer-aided design (CAD), Desktop Publishing,Paint/Image Editing, Video and Audio Editing, Multimedia

Authoring and Web Page Authoring

Communication E-mail, Web Browsers, Chat Rooms, Newsgroups, InstantMessaging, Groupware and Video Conferencing

These software application comes in packages.

SOFTW ARE APPLI CATI ONS PACKAGES

Sof t w ar e Ap p l i cat ion Ex am ples o f Pop u lar Pack ages

Word Processing Microsoft Word and Lotus Word Pro

Spreadsheet Microsoft Excel and Lotus 1-2-3

Database Microsoft Access and Microsoft Visual FoxPro

Presentation Graphics Microsoft Power Point and Lotus Freelance Graphics

Personal Information Manager Microsoft Outlook and Palm Desktop

Software Suite Microsoft Office and Lotus SmartSuite

Project Management Microsoft Project and Corel CATALYST

Accounting MYOB and Peachtree Complete Accounting

HOME AND EDUCATI ON

COMPUTERS FOR HI GHER EDUCATI ON

BUSI NESS

COMPUTERS I N BANKI NG

In the banking sector, many financial institutions offer online banking. People can access

their financial records from anywhere in the world. One example of online banking isMaybank2u. (www.maybank2u.com)

I NDUSTRY

By using the CAM system, computers record actual labour, material, machine and computertime used to manufacture a particular product. Computers process this data andautomatically update inventory, production, payroll and accounting records on thecompanys network.

GRAPHI CS AND MULTI MEDI A

Computers are crucial in publishing especially in the process of making works available tothe public. These works include magazines, books, newspapers, music and film production.

Special software applications are used to assist graphic designers to develop graphics,

texts, photographs and composing songs.

Computer-Aided Design, Desktop Publishing, Paint/Image Editing, Video and Audio Editingand Multimedia Authoring are among the popular applications software.


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COMMUNI CATI ON

A government provides society with direction by making and administering policies. Most

government offices or agencies have websites in order to provide citizens with up-to-date orlatest information.

People can access government websites to:

check information on taxes (www.hasil.org.my) apply for permits and licenses (www.jpj.gov.my)

COMPUTERS I N TOURI SM

Today, people will go online to get all related information about traveling. They can visitwebsites to get information on destinations, prices, hotels, flights and car rentals.They can also purchase ticket online, all payments can be made by using credit card.

COMPUTERS I N TH E HEALTHCARE

In the medical field, computers are very important in running the operations. Medical staffsuse computers for various purposes, namely:

maintaining patient records monitoring patients vital sign

assisting doctors, nurses and technicians with medical tests by using computer andcomputerised devices .

using medical software to help with researching and diagnosing health conditions.

SCI ENCE

In the scientific world, computers are used in all fields of science from biology to astronomyto meteorology and others. These are things thatcan be done by computers, namely:

collecting, analyzing and modelling data

serving as medium of communication with colleagues around the world contributing to new inventions or breakthrough in surgery, medicine and treatment

LESSON 22

COMPUTER USERS

HOM E USER

The computer is a basic necessity. Each home user spends time on the computer fordifferent reasons:

business communication

entertainment education

SMALL OFFI CE/ HOME OFFI CE ( SOHO) USER

SOHO users use computer to manage their work effectively. They advertise their productsand services through websites. They also take orders from the websites.These SOHO users:

use desktop or notebook computers as well as telephone, handphones and PDAswork in a small company or work as an individual at home

MOBI LE USER

include real estate agents, insurance agents, meter readers and journalists use notebook computers, Internet-enabled PDAs or smart phones

work with basic business software such as word processing and spreadsheetbusiness software

use presentation graphics software to create and deliver presentations to a large

audience by connecting a mobile computer or device to a video projector


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POW ER USER

include engineers, scientists, architects and virtual reality animators

use computers with extremely fast processor, bigger storage and customisedsoftware

work with mini computers that uses design to meet the organisational needs

use software such as CAD, CAM and MATLABExamples :

LARGE BUSI NESS USER

bank, insurance company, hypermarket use computers for basic business activities

have e-commerce that allow customers and vendors to interact and do businesstransactions online therefore customers, vendors and other interested parties canaccess information on the web

have e-mail and web browsers to enable communications among employees,vendors and customers

provide kiosks in public locations

Many employees of large business telecommute, which means they work away from their

offices workstation. They also have flexible schedule.

LESSON 26

TOPI CS FOR STUDY

In order to do the research, you need to follow this 5 steps.

STUDY TOPI CS

SOURCE CI TATI ON CARD

CREATI NG YOUR PRESENTATI ON

have at least 15 slides (not including the Title slide)

have a Title slide- introduce presentation- include names of each member of the team

use any design templates

use at least 5 graphics (e.g.: clip art, photographs, word art and drawings) have some multimedia

- use animation on slides (be careful of very noisy ones!)- use slide transitions

use less text on the slides- try presenting the information through pictures, graphs, mind maps or anyother form of visual (as oppose to textual) presentation

have a citation slide- the last slide must list all of your citations and other related resources (whereyou got the content)

- remember to give credit to others!

THE FI NAL PRESENTATI ON

Guidelines: each team member must speak during the presentation. each team will have 10 minutes to present. presenters should face the audience and not just read from the screen or paper.

Tips: practice in advance.

prepare notes on paper or cue cards to help you remember what you need to sayduring the presentation.

remember to speak out clearly for people at the back to hear you.

do not shout!


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LESSON 27

OVERVI EW OF COMPUTER SYSTEM

COMPUTER SYSTEM

A computer system is defined as combination of components designed to process data and

store files. A computer system consists of four major hardware components; input devices,output devices, processor and storage devices.

A computer system requires hardware, software and a user to fully function.

COMPUTER HARDW ARE

Computer hardware consists of: input devices, processor, output devices, storage devices

I n p u t De vi ce s : Keyboard , Light Pen , Joystick, Microphone, Mouse, Video, Digital camera.

Processor

The CPU is an example of a processor. It has the same important as the brain to humanbeing.

Ou t p u t D ev i ce s : Printer, Plotter, Speaker, Monitor

Sto rage Dev ices

Storage usually means secondary storage. It consists secondary storage devices such ashardisk, Floppy Disk, diskette, CD ROM and DVD ROM.

COMPUTER SOFTWARE

There a 2 types of computer software, system software and application software. Systemsoftware is any computer software that helps to run computer system. System software

controls, integrate and manages the individual component of a computer system.

LESSON 28I NTRODUCTI ON TO COMPUTER SYSTEM

COMPUTER HARDW ARE BLOCK DI AGRAM An Input device feed raw data to theprocessor. A processor processes raw data and turns it into useful information. A storagedevice keeps or stores both process and unprocess data for later usage. An output device

shows or display the processed data.

I NPUT DEVI CES

When data is entered into the computer system, it is called an input. Input

Keyboard, mouse, scanner, barcode reader and digital camera are some example of inputdevices.


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OUTPUT DEVI CES

Output is the result of raw input data that has been processed by the central processing

unit into meaningful information. Common forms of output are texts, numbers, graphics,sounds, animations and videos.The most common output devices are computer screens,speakers and printers.

STORAGE DEVI CESThe systems primary storage, Random Access Memory (RAM) can only hold datatemporarily. Thus, secondary storage is needed to provide additional storage. The datastored in the secondary storage is considered permanent until it is deleted or removed.

Secondary storage can be magnetic disks and optical disks. Examples of secondary storageare hard disks, rewritable CDs and DVDs as well as removable disks such as pen drives.

PERI PHERAL DEVI CES

External hardware devices attached to the computer are called peripheral equipments.

LESSON 29

I NFORMATI ON PROCESSI NG CYCLE

Do you know how a computer works? We use the computer in our everyday lives but not allof us know how this machine operates.

Human uses the brain to think, make decisions and process information. A computer has abrain too, and the brain of a computer is the processor or the central processing unit (CPU)that processes information.

THE CENTRAL PROCESSI NG UNI T

The central processing unit or the CPU is the brain of the computer.All processing activities are done in the CPU. It utilises the computer memory to execute

instructions from the application software and accomplish a task. For example: editing aletter, drawing a picture and sorting numbers.

The processor must be connected to input devices, output devices and storage devices tocarry out the above mentioned tasks.

THE I NFORMATI ON PROCESSI NG CYCLE

User will input the data to be processed by the processor. The storage holds databases, filesand programs. The output devices present the processed data as useful informationproducts for the user.

I NPUT

Input is any data or instructions that we enter into the computer system for processing.

There are some common ways of feeding input data into the system, which are: typing on a keyboard

pointing with a mouseCPU accepts instruction from the user and translates the instruction into readableinformation (decode).

PROCESS

The processing unit controls all activities within the system. For every instruction, thecontrol unit repeats a set of four basic operations called the machine cycle:

Fetch ing

the process of obtaining a program instructions or data item from memory.

Decoding

the process of translating a program instruction into signals that the computer can execute.


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Execut ing

the process of implementing the instructions in a program.

Sto r i ngthe process of writing the result to the storage or memory.

STORAGEStorage is a location which data, instruction and information are held for future use. Everycomputer uses storage to hold system software and application software.

When we issue a command to start the application software, the operating system locatesthe program in storage and loads it into memory.

A storage medium, also called secondary storage is the physical material in the computerthat keeps data, instruction and information.

A storage device is the computer hardware that records or retrieves items to and from

storage media.

OUTPUT

Output is data that has been processed into a useful form, called information. There arefour types of output, which are texts, graphics, audio and video.

The text consists of characters that are used to create texts, sentences and paragraphs.

Graphics are digital representations of non text information such as drawings, charts andphotographs.

Audio is music, speech or any other sound. Video consists of images thatprovide the appearance of full motion.

LESSON 30

DATA REPRESENTATI ON

BI NARY D I GI T

Computers recognize only two discrete states: on and off. Thesestates can be represented by two digits, 0 and 1. Each 0 or 1 iscalled a bit in the binary system.

Bit is the smallest unit of data a computer can process. Bit is ashort for binary digit. The binary system has a base of 2 with the two digits (0 and 1).

Combinations of 0s and 1s represent larger numbers.

BI T

A bit is the smallest unit of data that the computer can process. Bit is a short for binary

digit. A bit is represented by the numbers 1 and 0. These numbers represent the binarysystem. They correspond to the states of on and off, true and false, or yes and no.

BYTE

Byte is a unit of information built from bits. One byte is equals to 8 bits. Eight bits that aregrouped together as a unit. A byte provides enough different combinations of 0s and 1s torepresent 256 individual characters.

One byte represents a single character such as the number 3, letter b or a $ symbol. Bits

and bytes are the basis for representing all meaningful information and programs oncomputers.


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CHARACTER

One byte represents one character such as A, 7, 9 and +.Eight bits that are grouped

together as a unit. A byte provides enough different combinations of 0s and 1s to represent256 individual characters.

For example, the capital letter F is represented by the binary code 01000110 that can be

understood by the computer system. Eight bits grouped together as a unit are called a byte.A byte represents a single character in the computer.

CHARA CTER CODES

There are three character codes to represent characters which are ASCII, EBCDIC andUnicode. Each byte contains eight bits. A byte provides enough

LESSON 31

I NTRODUCTI ON TO BI NARY CODI NG

COMMUNI CATI ON CODES

Smoke signals, Morse code and semaphore are some of the communication codes used bypeople in the early days. In the information digital era, people send information via

electronic devices such as through the computers.

Computers use binary codes to communicate. One of the widely used binary codes is theA m e r i c an St a n d a r d Co d e f o r I n f o r m a t i o n I n t e r c h a n g e ( A SCI I ) .

HI STORY OF CHA RACTER CODES

Before people used binary codes such as ASCII to communicate via computers, charactercodes were widely used as a medium of communication. Lets look at some of the charactercodes used prior to the use of ASCII.

WHAT I S ASCI I ?ASCII pronounced as "ask-key" stands for the American Standard Code for InformationInterchange and was proposed by ASA (American Standard Association) in 963 and wasfinalised in 1968.ASCII is a standard of 7-bit code used to represent characters, whichinclude letters, numbers and punctuation marks.

LESSON 32

DATA MEASUREMENT

8 b it s = 1 b y t e

KI LOBYTE ( KB)

In mathematics, 1 KB = 1000 bytes.In computer, 1 KB = 1024 bytes or

can be said as:1 K B = 2 1 0 b y t e s

This is how we get the calculation for 1024 bytes.

MEGABYTE ( MB)

1 MB = 1 048 576 bytes or it can be said as:1 M B = 2 2 0 b y t e s

GI GABYTE (GB)

1 GB = 1 073 741 824 bytes or it can be said as: 1 GB = 2 3 0 b y t e s

TERABYTE (TB )

1 TB = 1 099 511 627 776 bytes or it can be said as:1 TB = 2 40 b y t e s


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LESSON 33

CLOCK SPEED MEASUREMENT

EVOLUTI ON OF COMMUNI CATI ONWhen people talk about a computers speed, they mean how fast it can process data. Inother words, this means the speed the computer can turn data into information.

Every microprocessor contains a system clock. The system clock controls the speed of allthe operations within a computer. The speed of the clock is measured by how many cyclesper second the clock makes.

HERTZ AND SECONDS

The clock speed unit is measured in hertz. A hertz is one cycle per second.

MEGAHERTZ ( MHz )

Mega is a prefix that stands for million. Thus, megahertz (MHz) equals to one million cyclesof the system clock. A computer that operates at 933 MHz (megahertz) has 933 million

clock cycles in one second.

GI GAHERTZ (GHz)

Giga is a prefix that stands for billion.Gigahertz (GHz) equals to one billion cycles of thesystem clock.In relation with megahertz,1.0 GHz is equivalent to 1000 MHz.

PROCESSI NG SPEED

The system clock is one of the major factors that influence the computer speed. A CPU witha higher clock speed can process more instructions per second than a CPU with a lowerclock speed. For example, a 1 GHz CPU is faster than a CPU operating at 800 MHz. Thespeed of the system clock affects only the CPU. It has no effect on peripherals such as aprinter or disk drive.

MI CROPROCESSOR SPEEDOne way of comparing the performance of personal computers is by comparing theirmicroprocessor speeds. Microprocessor speeds are determined by their clock speed and areusually expressed in gigahertz (GHz), billion of machine cycles per second.Thus, it is accurate to say that a Pentium 4 running at 2.4 GHz is approximately one-third

faster than a Pentium 4 running at 1.8 GHz.

SPEED AND PATH

The combination of speed and number of paths determines the total processing speed orchannel bandwidth. This is because different processorsoften use different architectures. For this reason, a 1.4 GHz Pentium 4 performs better thana 1.4 GHz Pentium 3, but it is not as fast as a 1.4 GHz Power PC G4 processor.

LESSON 34

I NPUT DEVI CES

I NPUTInput is any data or instruction that you enter into the memory of a computer.

There are four types of input: which are text, graphic, audio and video.

I NPUT DEVI CES

A keyboard is an example of input device for text input.A scanner is an example of input device for graphical as well as text input.

A microphone is an example of input device for audio input and a webcam is an example ofan input device for video input.A mouse is also an input device but it is called a pointing device used to input data that iscontinuous and multi-dimensional into a computer.


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a) I NPUT DEVI CES FOR TEXTS

You can enter data such as text and commands into a computer by pressing the keys on the

keyboard. You can press the keys of a virtual keyboard on the screen.

An optical reader is a device that uses a light source to read characters, marks and codesand then converts them into digital data that a computer can process.

b) I NPUT DEVI CES FOR GRAPHI CS

A scanner is a device that captures images from photographic prints, posters, magazinepages and similar sources for computer editing and display.

A digital camera allows you to take pictures and store the photographed images digitally.

c) I NPUT DEVI CES FOR AUDI OAudio input is the speech, music and sound effects entered into the computer. This can bedone using input devices such as a microphone and digital musical instruments like theMusical Instrument Digital Interface (MIDI) keyboard.

d) I NPUT DEVI CES FOR VI DEO

Video input is input of motion images captured into the computer by special input devices.

A Closed-Circuit Television (CCTV) video camera is a type of digital video camera thatenables a home or small business user to capture video and still images.A webcam is any video camera that displays its output on a web page.A digital video camera allows you to record full motion and store the captured motiondigitally.

e) POI NTI NG DEVI CES

A pointing device is another form of input device. Pointing devices such as a mouse,

trackball, graphics tablet and touch screen are used to input spatial data into the computer.

Spatial data refers to data that is continuous and multi-dimensional.

LESSON 35

OUTPUT DEVI CES

Output is the result of data processing activity when it is presented external to the system.

OUTPUT DEVI CES

An output device is hardware that is capable of delivering or showing information to one or

more users. An output device shows, prints and presents the results of a computers work.

TYPES OF OUTPUT D EVI CES

A display device is an output device that visually conveys texts, graphicsand video information. A printer is an output device that prints text and graphics on aphysical medium such as paper or transparency film.An audio output device produces

music, speech, or other sounds.

Other output devices include Liquid Crystal Display (LCD) projectors and facsimile (fax)machines. A monitor is an example of an output device that can be used to display text. Itcan also display graphics and video. It is similar to a television set that accepts videosignals from a computer and displays information on its screen.

A printer is another example of an output deviceA photo printer is a colour printer that produces photo-lab-quality pictures.


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LESSON 36

MOTHERBOARD

This is a motherboard and its components. Motherboard is the maincircuit board of the system unit, which has some electronic componentsattached to it and others built into it.

This is the location of the Central Processing Unit (CPU).

This is where the expansion slots are located.

These are the Peripheral Component Interconnect (PCI)expansion slots. Peripheral Component Interconnect. A personalcomputer local bus which runs at 33 MHz and supports Plug and Play. Itprovides a high-speed connection with peripherals and allows connectionof seven peripheral devices

In addition, the Industry Standard Architecture (ISA) expansion slotsare also the components of the motherboard. Industry Standard

Architecture. A PC expansion bus used for modems, video displays,speakers, and other peripherals. PCs with ISA commonly have some8-bit and some 16-bit expansion slots.

These are the expansion card. The expansion cards are slotted in the

expansion slots.

This is called RAM or Random Access Memory. RAM is the memory of

the computer.

This is the location of the ports. Connectors are plugged into theseports. Port is Point at which peripheral attaches to a system unit so itcan send data to or

receive information from the computer.

The connector connects to the port. For example, the printer port matches its connector. Allcomputer components are connected to its respective ports by a connector.


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LESSON 37

COMPONENTS OF A MOTHERBOARD

CENTRAL PROCESSI NG UNI T ( CPU)

The Central Processing Unit (CPU) controls the operation of the computer.It interprets and carries out the basic instructions that operate acomputer. The processor significantly impacts overall computing powerand manages most of a computer's operations.

On larger computers such as mainframes and supercomputers, the various functions

performed by the processor extend over many separate chips and often multiple circuitboards. On personal computer, all functions of the processor usually are on a single chip.Some computers and chip manufacturers use the term microprocessor to refer to a personalcomputer processor chip.

EXPANSI ON SLOTS

Expansion slots are the sockets where the circuit boards or the adapter cards can beinserted into the motherboard. In computers, a slot or expansion slot, is an engineeredtechnique for adding capability to a computer in the form of connection pinholes (typically inthe range of 16 to 64 closely-spaced holes).

It is a place to fit an expansion card containing the circuitry that provides some specialisedcapability, such as video acceleration, sound or disk drive control.

A Peripheral Component Interconnect (PCI) bus is a high speed expansion bus that connects

high speed devices.

An Industry-Standard Architecture (ISA) expansion slot is a slot in a computer where ISAaccessories can be added to.

EXPANSI ON CARDS

An expansion card is plugged into an expansion slot. It is used to add new devices or

capabilities to a computer.

An expansion card is a circuitry designed to provideexpanded capability to a computer. It is provided on the surface of a

standard-sized rigid material (fiberboard) and then plugged into one ofthe computer's expansion slots in its motherboard (backplane).

Cards may come in one of two sizes designed to match standard slot dimensions. Cardsmay come in one of two sizes designed to match standard slot dimensions.RAM SLOT

The slot where the computer memory, also called as RAM is placed on

the computers motherboard.


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PORTS AND CONNECTORS

A port is the point at which a peripheral attaches to a system unit sothat the peripheral can send data to or receive information from thecomputer.

An external device, such as a keyboard, monitor, printer, mouse andmicrophone is often attached by a cable to a port on the system unit.

The back of the system unit contains so many ports. Some newer personal computers also

have ports on the front of the system unit.

LESSON 38

PORTS AND CONNECTORS

There are different kinds of port in a system unit. The ports are :

Serial port

Parallel portUniversal Serial Bus (USB) port.

FireWire portspecial purpose ports

- MIDI port- SCSI port- IrDA port

1) SERI AL PORT

A serial port is a socket on a computer used to connect a modem, data acquisition terminalor other serial devices via a slow-speed serial interface.

2) PARALLEL PORT

A parallel port is a socket on a computer used to connect a printer or other parallel devicesvia the computer's parallel interface.

3) USB PORT

A USB port is a socket on a computer or peripheral devices into which a USB cable isplugged in. A USB port, short for universal serial bus port, can connect up to 127 differentperipherals together with a single connector.

It's used to connect all kinds of external devices, such as external hard drives, printers,

mouse and scanner. It can transfer data to a speed of 12 megabits per second.

4) USB PORT

Previously the FireWire port is called IEEE 1394 port, a personal computer (and digitalaudio/video) serial bus interface standard.

FireWire is similar to a USB port in that it can connect multiple types of devices that requirefaster datatransmission speeds. Usually camcorders and other video equipment use this port totransmit data on a computer. Data can move across the port at up to 400 megabits persecond.

Daisy-ChainA bus wiring scheme in which, for example, device A is wired to device B, device B is wiredto device C, device C to device D etc.


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5) SPECI AL PURPOSE PORTS

There are four special purpose ports, which are:

M I D I p o r t

It is designed to connect the system unit to a musical instrument,

such as an electronic keyboard.

SCSI p or t

It is a special high-speed parallel port used to attach peripheraldevices such as disk drives and printers..

I r D A po r t

Some devices transmit data via infrared light waves. For these

wireless devices to transmit signals to a computer, both the

computer and the device must have an IrDA port.

LESSON 39

CENTRAL PROCESSI NG UNI T

THE CENTRAL PROCESSI NG UNI T ( CPU)

Like human beings, computers too have a brain that processes raw informationA Central Processing Unit or CPU is a microprocessor (or processor for short). It is anintegrated circuit chip that is capable of processing electronic signals. The CPU is the mostimportant element in a computer system. A CPU interprets instructions given by thesoftware and carries out those instructions by processing data and controlling the rest of the

computers components.

A CPU consists of two subcomponents; the Control Unit (CU) and the Arithmetic Logic Unit(ALU).

FETCH

Retrieves the next program instruction from the computers memory.

DECODE

Determines what the program is telling the computer to do.

STORE

Stores the results to an internal register (a temporary storage location or to memory).

EXECUTE

Performs the requested instruction, such as adding two numbers or deciding which one of

them is larger.

2) ARI THMETI C LOGI C UNI T ( ALU)

The Arithmetic Logic Unit (ALU), as its name implies, can perform all arithmetic and logicaloperations. Arithmetic operation is an operation that forms a function of two numbers. Thisfunction is usually one of the class of operations: add, subtract, multiply and divide.

Logic operation is an operation on logical values, producing a Boolean result.In general there are 16 logic operations over one or two operands; they include AND, OR,

NOT, NAND, NOR, XOR and equivalence.


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HOW DAT A I S PROCESSED BY THE CPU

When a user starts a program, its instructions are transferred from the storage device tothe memory. The user enters the data needed by the program.

The Control Unit then interprets and executes instructions in the memory. The Arithmetic

Logic Unit then performs calculations on the data in the memory. As a result, information isthen stored in the memory. Information can then be sent to an output device or a storagedevice.

LESSON 40

STORAGE

W HAT I S COMPUTER STORAGE ?Information and documents are stored in computer storage so that it can be retrievedwhenever they are needed later on.

FUNCTI ONS OF COMPUT ER STORAGE.

Computer storage is important to help users store programs and data to be used at a latertime. It is also useful to keep current data while being processed by the processor until the

information is saved in a storage media such as a hard disk or a diskette.

TYPES OF COMPUTER STORAGE

Pr i m a r y s t o r a g e is known as the main memory of a computer, including RAM (Random-Access Memory) and ROM (Read-Only Memory). It is an internal memory (inside the CPU)that can be accessed directly by the processor.

Secondary s to r age is the alternative storage in a computer. It is an external storage thatrefers to various ways a computer can store program and data.

PRI MARY STORAGE

Primary storage is installed internally. Two main types of primary storage are RAM andROM. Data from RAM can be read or retrieved and written or stored during processingwhereas data from ROM can just be read only.

RAM is volatile, which means the program and data will be lost when thecomputer is turned off.

ROM is non-volatile which means it holds the programs and data even when the computer isturned off.

volatile : The content is lost wh en a comput ers power is tur ned off.

SECONDARY STORAGE

Secondary storage is an alternative storage. It is very useful to store programs and data forfuture use. Secondary storage is required for two reasons.

1. The working memory of the CPU is limited in size and cannot always hold theamount of data required.

2. Data and programs in secondary storage do not disappear when the power is turnedoff.


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LESSON 41

PRI MARY STORAGE

Primary storage is the main memory in a computer. It stores data and programs that canbe accessed directly by the processor.

TYPES OF PRI MARY STORAGE

There are two types of primary storage which are RAM and ROM.

RAM is an acronym for Random-Access Memory which means the data and program in RAMcan be read and written.

ROM is an acronym for Read-Only Memory. The data or program in ROM can just be readbut cannot be written at all.

RANDOM -A CCESS MEMORY (RAM )

RAM is installed inside computers. RAM is also known as a working memory.The data in RAM can be read (retrieved) or written (stored).

RAM is volatile which means the programs and data in RAM are lost when thecomputer is powered off.A computer uses RAM to hold temporary instructions and data needed to completetasks. This enables the computer's CPU (Central Processing Unit) to accessinstructions and data stored in the memory very quickly.RAM stores data during and after processing.

READ-ON LY MEMORY ( ROM)

ROM is another type of memory permanently stored inside the computer.ROM is non-volatile. It holds the programs and data when the computer is powered

off.Programs in ROM have been pre-recorded. It can only be stored by themanufacturer; once it is done, it cannot be changed.Many complex functions, such as start up operating instructions, translators for high-level languages and operating systems are placed in ROM memory.

All the contents in ROM can be accessed and read but cannot be changed.

DI FFERENCES BETWEEN RAM AN D ROM

RAM ROM

Data and program Stores during and afterprocessing

Stored by manufacturer

Content Stores informationtemporarily

Stores instructions (Information)permanently

Processing time Very fast, but uses a lotof power

Fast, but uses very little power

Volatility Volatile Non-volatile


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LESSON 42

SECONDARY STORAGE

W HAT I S SECONDA RY STORAGE?

Secondary storage is another alternative storage to keep your work and documents. It is

very useful to store programs and data for future use.

It is non-volatile, which means that it does not need power to maintain the informationstored in it. It will store the information until it is erased.

TYPES OF SECONDARY STORAGE

MAGNETI C MEDI UMMagnetic Medium is a non-volatile storage medium. It can be any type of storage mediumthat utilizes magnetic patterns to represent information. The devices use disks that arecoated with magnetically sensitive material. The examples of magnetic storage are:

magnetic disk such as:o a floppy disk, used for off-line storage

o hard disk, used for secondary storagemagnetic tape; including video cassette, audio storage reel-to-reel tape and others.

OPTI CAL MEDI UM

Optical Medium is a non-volatile storage media that holds content in digital form that arewritten and read by a laser. These media include various types of CDs and DVDs.

These following forms are often commonly used :

CD, CD-ROM, and DVD: Read only storage, used for distribution of digitalinformation such as music, video and computer programs.CD-R: Write once storage, the data cannot be erased or written over once it is

saved.CD-RW, DVD-RW, and DVD-RAM: Slow to write but fast reading storage; it allowsdata that have been saved to be erased and rewritten.

Optical media have a number of advantages over magnetic media such as the disk capacity.One optical disk holds about the equivalent of 500 floppy disks worth of data. Durability isanother feature of optical media, they are able to last for up to seven times as long astraditional storage media.

FLASH MEMORY

Flash Memory is a solid-state, non-volatile, rewritable memory that functions like RAM and

a hard disk drive combined. Flash memory store bits of electronic data in memory cells justlike DRAM (Dynamic RAM), but it also works like a hard disk drive that when the power isturned off, the data remains in the memory. Flash memory cards and flash memory sticks

are examples of flash memory.

Flash memory cards are also used with digital cellular phones, MP3 players, digital videocameras and other portable digital devices.

The advantages of flash memory are, it offers fast reading access times among thesecondary storage devices, (though not as fast as RAM) it is durable and requires lowvoltage. It is also light and small. The disadvantage is, it is more expensive than the

magnetic disk of the same capacity.


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LESSON 43

TYPES OF SOFTWA RE

Software is a program which consists of a set of instructions that tells the computer how toperform a specific operation.

A computer is just a machine with no special benefits without software.

CATEGORI ES OF SOFTW ARESoftware can be divided into two categories, which are:

Sy s t e m So f t w a r e

Software that is used to control and manage computer devices and operations.

App l i ca t i on So f tw are

Software that is used to help a user perform a task and solve a problem.

SYSTEM SOFTWARE

System software refers to all programs that help the computer to function properly. Themost important type of system software is the computers operating system, which enables

the computer to start, such as Microsoft Windows, MS-DOS and Mac OS.Other types of system software include system utilities such as file compression (zipprogram) and antivirus programs.

APPLI CATI ON SOFTWARE

Application software are all programs that perform specific tasks for users, which includeword processing, spreadsheet, database, presentatione-Mail and Web browser software. Examples of application software are Microsoft Word,Microsoft Excel, Outlook Express and Internet Explorer.

SYSTEM SOFTW ARE VS APPLI CATI ON SOFTWA RE

The differences between system software and application software.


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LESSON 44

SYSTEM SOFTWARE

W HAT I S SYSTEM SOFTW ARE

A system software is a program that controls or maintains the operations of a computer and

its devices. A system software also serves as the interface between the user, the applicationsoftware and the computers hardware.

There are two types of system software:

operating system utility program

OPERATI NG SYSTEM

An operating system is a set of programs that coordinates all the activities among thecomputer hardware devices. In most cases, the operating system is installed and resides on

the computers hard disk.

However, on handheld computers and many mobile devices such as PDAs and smartphones, the operating system may reside on a ROM chip.

The operating system that a computer uses sometimes is called the platform.

L inux is a freely distributed UNIX, it is a compatibleoperating system for PCs and a number of other processors.

M ac OS X is a multitasking operating system that is the latest version of the Macintoshoperating system.

U N I X is an operating system, or family of operating systems, developed at BellLaboratories in early 1970sas a replacement for an earlier system called Multics.

W i n d o w s XP is the latest version of the Windows operating system, which is Microsoftsfastest, most reliable Windows operating system.

UTI LI TY PROGRAM

A utility program which is also called a utility is a type of system software that allows a userto perform maintenance-type tasks usually related to managing a computer, its devices orits programs.

ANTI VI RUS, DI AGNOSTI C UTI LI TY, FI LE MANAGER, SCREEN SAVER


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THE DI FFERENCES BETW EEN OPERATI NG SYSTEMS AND UTI LI TY PROGRAM

LESSON 45

TYPES OF OPERATI NG SYSTEMS

DEFI NI TI ON OF OPERATI NG SYSTEM

An operating system is a set of programs that schedule tasks, allocates storage andpresents a default interface to the user between applications. Many of the first operatingsystems were device-dependent and proprietary.

PC PLATFORM OPERATI NG SYSTEMS

There are various types of operating system used on different platforms. The examples ofoperating systems used on PC platforms or IBM compatible computers are:

Disk Operating System (DOS)

Microsoft Windows XP

Microsoft Windows XPs operating environment is a Graphical User Interface (GUI). It is a

closed source software.

APPLE PLATFORM OPERATI NG SYSTEMS

The operating systems used on Apple platforms are:

Mac OSMac OS X

CROSS-PLAT FORM OPERATI NG SYSTEMS

Cross-platforms operating systems are:UNIXLINUX

Linux is a popular, free, UNIX-like graphical user interface operating system. It is an open

source software. Linux follows the Free Software Foundation's radical licensing model, whichprovides a great deal of liberty to those that interact with Linux technology.


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LESSON 46

FUNCTI ONS OF OPERATI NG SYSTEMS

DEFI NI TI ON OF OPERATI NG SYSTEM

An operating system, also commonly called OS is a set of programs that coordinates all the

activities among computer hardware devices. It also supports the application software thatwe run.

It is designed to work with a specific type of computer such as a PC or a Macintosh.

Examples of popular Operating Systems are:-Disk Operating System (DOS)Linux

Mac OS XUnixWindows XP

FUNCTI ONS OF OPERATI NG SYSTEM

1) Starting The Computer

2) Providing A User Interface

3) Managing Data And Programs

4) Managing Memory

5) Configuring Devices

LESSON 47

I NTRODUCTI ON TO COMPUTER SYSTEM

THE I MPORTANCE OF USER I NTERFACES

The user interface is the part of an operating system that you see and interact with and by

which users and programs communicate with each other.

The importance of user interfaces are:to assist users interacting with a softwareto control how a user enters data and instructionsto control how information is displayed

COMMAND -LI NE USER I NTERFACEThe command-line user interface requires a user to type commands or press special keys onthe keyboard to enter data and instructions that instruct the operating system what to do.It has to be typed one line at a time.

MENU DRI VEN I NTERFACEMenu-driven user interface enables the user to avoid memorizing keywords such as copy,

paste and syntax. On-screen, menu-driven interface provide menus as means of enteringcommands. It shows all the options available at a given point in a form of text-based menu.Menu-driven user interfaces are easy to learn.

GRAPHI CAL USER I NTERFACE ( GUI )

Graphical user interface makes use of the computers graphics capabilities to make the

operating system and programs easier to use, which is also called user-friendly. On todaysPCs and Macintoshes, GUIs are used to create the desktop that appears after the operatingsystem finishes loading into memory.


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LESSON 48

TYPES OF APPLI CATI ON SOFTW ARE

TYPES OF APPLI CATI ON SOFTW ARE

COMMON TYPES OF APPLI CATI ON SOFTW ARE

Word Process ingWord Processing an office application that enables user to create, edit, format and print

textual document.

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