Network

Basic Concept of Network


What is Network?

Network is a collection of computers and devices connected together via communication devices and transmission media 

Computer Communications

Computer communications is a process in which two or more computers or devices transfer data, instructions, and information. Some communications involves cables and wires; others are sent wirelessly through the air.

Communications System

A Sending device that initiates an instruction to transmit data, instructions, or information.
A communication device that connects the sending device to a communications channel.
A communications channel, or transmission media on which the data, instructions, or information travel.
A communications device that connects the communications channel to a receiving device.
A receiving device that accepts the transmission of data, instructions, or information.

Advantages Using Network

Facilitating Communications
Using a network, people communicate efficiently and easily via e-mail, instant messaging and chat rooms.

Sharing Hardware
In a networked environment, each computer on the network can have access to all hardware on the network.

Sharing Data and Information
In a networked environment, any authorized computer user can access data and information stored on other computers on the network.

Sharing Software
Users connected to a network have access to software on the network.

Transferring Funds
Called electronic fund transfer (EFT), it allows users connected to a network to transfer money from one back account to another via transmission media.

Disadvantages of Using a Network

Viruses
When computers are connected by a network, the virus can spread itself electronically, at computer speed.

Network Failure
If the file server fails then no-one on the network can access any files or folders. This means that nobody can do any work. For an organisation, this would be extremely costly and disruptive.

Slow Service
As more users log onto the network and requests files, sends things to be printed and open more software applications, the network can start to slow down.

Cost
Every workcard to enable it to be connected to the network. Other hardware such as hubs, switches and routers are often needed.

Expert Support Required
Networks need constant monitoring to ensure that the performance is maintained and that all of the components are working properly. This requires specialist staff such as network managers and technicians who will spend all of their time ensuring that the network works efficiently whenever you need to use it. These staff add a large cost to running a network, but without them, things would start to fail.        

What is Output?

Read This

Output is data that has been processed into a useful form.

Output Device

An output device is any type of hardware component that conveys information to one or more people. 

Display Devices

A display device visually conveys tect, graphics, and video information. 
A monitor is packaged as a separate peripheral 
   - LCD monitor
   - Widescreen
A CRT monitor is a desktop monitor that contains a cathode-ray tube. It has a much larger footprint than do LCD monitors.
Televisions also are a good output device. It requires a converter if you are connecting your computer to an analog television.
Digital television (DTV) offers a crisper, higher-quality output.
HDTC is the most advanced form of digital television.

Printers

A Printer produces text and graphics on a physical medium. Printed information is called a hard copy, or printout. Landscape or portrait orientation.
Examples: Ink-jet printers, dot-matrix printers, photo printers, laser printers, thermal printers, mobile printers, label and postage printers, plotters, and large-format printers.

Speakers, Headphones and Earbuds

Some Speakers are specificalle designed to play audio from a portable media player for example an iPod dock.
Voice Output occurs when you hear a person's voice or when the computer talks to you through the speakers. Some web sites indicate themselves providing voice output. It often works with voice input. VoIP uses voice output and input.

Data Projector



A Data Projector is a device that takes the text and images displaying on a computer screen and projects them on a larger screen. Which is LCD projector and Digital Light Processing (DLP) projector.

Interactive Whiteboard

An Interactive whiteboard is a touch-sensitive device, resembling a dry-erase board, that displays the image on a connected computer screen.     

What is Input?

Welcome again!

Input is any data and instructions entered into the memory of a computer. Instructions can be entered into the computer in the forms of programs, commands, and user responses.

Input Devices

An input device is any hardware component that allows users to enter data and instructions into a computer.

Examples: 

1. Keyboard
2. Pointing Devices
     *Mouse
     *Trackball
     *Touchpad
     *Pointing Stick
3. Microphone
4. Scanner
5. Webcam
6. Touch Screens
7. Joystick
8. Digital Camera
9. Reading Devices
     *Optical Character Recognition (OCR)
     *Optical Mark Recognition (OMR)
     *Magnetic-Ink Character Recognition (MICR)
     *Biometric input device

Keyboard

A keyboard is an input device that contains keys users press to enter data and instructions into a computer. 

There are three types of keyboards which is: Desktop computer keyboard, Keyboard for mobile devices, and Keyboard ergonomics.

Pointing Devices 

A pointing device is an input device that allows a user to control a pointer on the screen. A pointer is a small symbol on the screen whose location and shape changes as a user moves a pointing device.

Pointing devices are used to move the insertion points; select text, graphic, and other objects; and click buttons, icons, links and menu commands.  

Web Cam

A web cam is a type of digital video camera that enables user to capture videos and still images, send email messages with video attachments, add live images to instant messages, broadcast live images over the internet and make video phone calls.

Scanners and Reading Devices

Optical Character Recognition (OCR) involves reading characters from ordinary documents. A turnaround document is a document you return to the company that creates and sends it.
Optical Mark Recognition (OMR) reads hand-draws marks such as small curciles or rectangles. An OMR device scans the documents and matches the patters of light.
A Bar Code Reader, also called Bar Code Scanner uses laser beams to read bar codes.
RFID (Radio Frequency Identification) uses radio signals to communicate with a tag placed in or attached to an object. An RFID reader reads information on the tag via radio waves.
Magnetic Stripe Card Readers read the magnetic stripe on the back of cards such as credit cards and bank cards.
MICR (Magnetic Ink Character Recognition) devices read text printed with magnetized ink. An MICR reader converts MICR characters into a form the computer can process. Banking industry uses MICR for check processing.

Biometric Input

Biometric authenticates a person's identity by verifying a personal characteristic. Like fingerprint reader, face recognition system, hand geometry system, voice verification system, signature verification system, iris recognition system and retinal scanners.   

Computer System

Computer System!

Hey there, again!

Welcome back. Today we are going to tell you all about Computer System.

What is a computer system? It is a complete, working computer which includes operating system, software and hardware to make the computer function.

In computer system, we have data and information. Data is a collection of unprocessed items. (text, numbers, images, audio, video). Where as, information conveys meaning and is useful to people.

The process of converting data into information is called an 'Information Process Cycle' which consists of:

a) Input - Any data instruction entered into memory of computer.

b) Process - Transform an input data flow into an output data flow. 

c) Output - Data that has been processed into a useful form.

d) Storage - Hold data instructions and information for future use.

Imformation Process Cycle is the series of input, process, output and storage activities. The computer will process data (input) into information (output) and holds data, information and instructions in storage for future use.

Welcome!

Hey There!

This is our very first blog on Computer Science subject. But before we begin, we will introduce ourselves.

Our group consists of 4 people. There is Nad, Sha, Mika Yaya and myself, Syidah. 

~Syidah~

In short, I'm somewhat antisocial and I mostly hide or sneak around the web instead of going out in public places. And.... I LOVE CHOCOLATE!!!

~Nad~

nothing much to say , just an ORDINARY PERSON ( haha ) . love to laugh but that is not good for us. k bye !

~Sha~

First of all,my real name is quite weird ,guess what ??? AREISHA WARHEIDA BT ENCIK ARIFF .I'm officially 18 years old now and always trying to be a good person >< . And last but not least,ILOVEMAGNUM !

~Mika Yaya~

annyeonghaseyo! ( hello!) im mika. So people used to call me this name. I found that they always happy when calling me mika. so keep calling me mika. :) :P