01. Basics of the information technology Section -01

A/L ICT Topic: 01                                                                                                               Section: 01 

Basics of the information technology

Information technology (IT) is a technology which uses computers to gather, process, store, protect, and transfer information. Today, it is common to use the term Information and communications technology (ICT) because it is unimaginable to work on a computer which is not connected to the network.

The computer consists of:

v hardware – physical computer parts, palpable and visible

v software – set of commands that are "understandable" to the computer; instructions to its palpable parts, giving orders what to do

Basic principle of computers:

Data enters the computer through one or more input devices. The computer then processes the data and transmits the resulting data to output devices. Output devices can be human interfaces such as a screen or another electronic device such as a storage device or computer network.

The system unit consists of the following components:

v Motherboard - MBO

·         a computer "backbone" responsible for communication between components and transmission of information

v  Central Processing Unit - CPU

·         functions: command execution, data transmission, computer function control

·         basic characteristics:

ü  speed (in Mega Hertz (MHz), Giga Hertz (GHz))

ü  amount of memory (Cache in Bytes)

v Random Access Memory - RAM

·         a memory container for programs that are currently running and data that is being processed

·         basic characteristics:

ü  speed (in MHz, GHz)

ü  capacity (in Bytes)

ü  data rate class (DDR SDRAM, SDR SDRAM)

v permanent memory:

·         Hard Disk Drive - HDD - device (memory) used for permanent data storage

Ø  data is stored on magnetic platters; electromagnetic heads are used for reading and recording data with the exception of the newest disk types called Solid State Drive (SSD)

Ø  basic characteristics:

ü  disk platters rotation speed (in RPM)

ü  capacity (in GB)

ü  connection interface (IDE, SATA)

Ø  Floppy Disk Drive - FDD

Ø  Optical disks - CD, DVD

v Graphics processing units (GPU)

Ø  Function: processing and displaying image on the monitor

Ø  It consists of a graphics processor and its own working RAM memory

Ø  Basic characteristics:

·         Type of graphics processing units (ATI Radeon, Nvidia GeForce, or other)

·         RAM size

·         Connection interface/slot type

Ø  ports:

·         Parallel Port

·         Serial Port

·         Universal Serial Bus (USB)

Input and output devices
Input devices:			Output devices:
	o	keyboard		o	monitor
	o	scanner		o	projector
	o	touchpad		o	printer
	o	mouse		o	plotter
	o	trackball		o	speakers
	o	joystick		o	earphones
	o	Microphone
	o	Stylus
	o	Camera (web, digital)

v  Device that is both input and output: touchscreen.

Common devices and media for storing and transferring data:

·         Hard disk                                              ● Network disk drive

·         USB flash drive                                    ● Online storage device

·         Diskette and ZIP diskette

·         CD and DVD discs

·         Memory cards

·         Internal hard disk

·         External hard disk

Software - a computer program which, as opposed to hardware, is an intangible part of the computer, written to perform a single or multiple tasks on computer using the built-in hardware.

v Software types:

Operating systems (OS) - the basic program on your computer that is automatically loaded when computer is started up:

·         Linux (Debian, Ubuntu, Fedora, Knoppix...)

·         Microsoft Windows (XP, Vista, 7...)

·         Mac OS X (Cheetah, Panther, Snow Leopard...)

v  Application software – some types of software that can be used on an installed operating system:

ü  Office programs - OpenOffice.org, LibreOffice, Microsoft Office

ü  Antivirus program – Avira, Sophos, and Kaspersky etc.

ü  Web browser: Mozilla Firefox, Microsoft Internet Explorer, Opera, Safari

v E -accessibility options:

ü  Voice recognition software,

ü  Screen reader,

ü  Magnifying tool,

ü  On-screen keyboard.

v Computer types:

ü  Mainframe Computer

·         Large, powerful and expensive computers,

·         Often used within large systems and organizations,

·         Can be used by more than one user simultaneously.

ü  Personal Computer – PC

·         First PC was made by IBM in 1981,

·         It was originally made for executing a single task by a single user at the time.

·         Today: a single person can execute many tasks simultaneously (multitasking).

ü  Apple Macintosh (Mac)

·         Personal computer made by Apple company,

ü  Laptop computer (notebook)

·         Relatively small computers, easily carried around,

·         Consists of LCD display and a small keyboard,

·         Do not fall behind PCs by their functions

ü  Personal Digital Assistant - PDA (Palm)

·         Small computers that can fit into a pocket or user's palm,

·         Meant for performing basic personal/business functions:

§  Managing personal or business tasks and assignments,

§  Maintaining the address book,

§  Accessing and browsing the Internet,

§  Sending/receiving e-mails, etc.

·   PDAs have now been replaced by modern smart phones that combine the features of a PDA with a mobile phone and camera.

ü  Network connected computer

·   Every computer (PC, notebook, PDA) connected to the network is considered a network computer;  can be connected either through network cable or through a phone line (at least to one more computer)

             ü Beside notebooks and palms, there are other portable digital devices:

·         Mobile phone

·   Smartphone – mobile phone with advanced functions such as e-mail, Internet browser, E-book reader

·         Multimedia player: iPod, iRiver, Zune