CHAPTER 2 - COMPUTER SYSTEMS

CHAPTER 2 - COMPUTER SYSTEMS

1.0  System concept
1.1  Define Computer Systems.

Computer is an electronic device, operating under the control of instructions stored its own memory,

• that can accept data (input),
• process the data according to specified rules (process),
• produce results (output),
• and store the results for future use (storage).

Meaning of input, process, output and storage.

1. Input - input is any data and instructions entered into the memory of a computer. There are four types of input which are:text, graphics, audio, and video.
2. Input device - Input device is any hardware component that allows users to enter data and intructions into a computer. Eg:keyboard, mouse, scanner, barcode reader. Also pointing device:mouse, joystick, trackball, touch screen, pointing stick and graphic tablets.'
3. CPU/central processing unit - CPU is an electronic component on a computer's motherboard that interprets and carries out the basic instructions that operate the computer. Eg: intel pentium IV, AMD Athlon, G4.
4. Output - output is data that has been processed into a useful form, called information.
5. Output device - Eg: speaker, monitor, LCD projector, p\printer, plotter.
6. Storage - storage is a location in which data, instructions, and information are saved for future use. Eg: CD ROM, diskette, hard disk.

PROCESS OF FILTERING...

The method of choice to limit access on the internet is to filter either by:-
     a)Keyword blocking
        The method uses a list of banned word or objects terms such as xxx ,sex and nude.As the page is downloading ,the filter searches for any these words.If found,it will blocked the page completely,stop downloading the page ,block the banned words an even shut down the browser.

      b)Site blocking
      This method use software to list the web sites that will be blocked by using software.The software also prevents users from being access the web sites on list.


     c)web rating system
     Web sites are rating in terms of nudity,sex,violence and language.The web sites rates can be done by setting the browser to only accept pages with certain level of ratings.

CONTROVERSIAL CONTENTS AND CONTROL..

2.6  Effect of controversial contents (PORNOGRAPHY and      SLANDER) on society :

Pornography
Pornography is any form of media or material (like books, video or photos) that show erotic behaviour and intended to cause sexual excitement. The effects of pornography on society are :

• Can lead to criminal acts such as exploitation of women.
• Can lead to sexual addiction.
• Can develop lower moral values towards other people.
• Can erode good religious, cultural, behaviours and beliefs.

        Slander
Slander is a false spoken statements about someone, intended to damage his or her reputation. The effects of slander on society are :

• Can develop society that disregards on honesty and truth
• Can lead to bad habits of spreading rumors and untruth
• Can cause people to have negative attitudes towards another person.

2.5 AUTHENTICATION TECHNOLOGIES..

Authentication is a process where user verifies their identity.Authentication deals with the problem of determining whether a user should be allowed access to a particular system. Four commonly authentication methods:

a. User identification (something you know - have to remember). User identification is a unique combination of 
character (letter, number or symbol) that identify specific user. Examples of user identification are pin number and password.

b. Possessed object (something you have - an object). A possessed object is any item that you must carry to gain access to computer or computer facility. Examples of possessed objects are ATM card, credit card, key,security token and smart card. The card you use in an automated teller machine (ATM) is a possessed object that allows access to your bank account. 

                              

c. Biometric device (something you are - part of user's body) is a devices that translates personal characteristic into digital code that is compared with the digital code stored in the database. E.g. of biometric devices are fingerprint reader, hand geometry reader, iris scanner, signature verification system. 

hand geometry reader

d. Callback system is a checking system that authenticates the user. The callback system is commonly used in the bank operation andbusiness transaction. For example, when you called a McDonald Delivery Services, the operator will ask you to hang up since he wants to link you with the other worker.

2.4 WAYS FOR MAKING PERSONAL DATA MORE PRIVATE

Below are list measures you can take to make your personal data more private.


1. Purchase goods with cash, rather than credit card.
2. Install personal firewall.
3. Clear your history file when you are finished browsing.
4. Have unlisted telephone number.
5. Fill in only necessary information on warranty and registration form.

2.3 INTELECTUAL PROPERTY LAW

Intellectual Property laws cover ideas, inventions, literary creactions, unique names, business modals, industrials processes, computer program codes and many more.

Four types Intellectual property
a. Patents for inventions
b. Trademark for brand identity
c. Copyright for materials

COMPUTERISED AND NON-COMPUTERISED SYSTEMS

COMPUTER SYSTEM

A system is an arrangement of elements that when it is put together it becomes an organised and established procedure. A system typically consists of components connected together in order to facilitate the flow of information, matter or energy.

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