wordprocessorsfor creating and editing texts, spreadsheetsfor calculating mathematical formulae

VB035 English I

UNIT 1 Computer Users

INTRODUCTION

A computeris a device that processes dataaccording to a set of instructions known as a program.The equipment is known as the hardwareand the programs and data are the software. A special set of programs, called an operating system, provides an interface for the user and allows applications

programsto communicate with the hardware. Common applications programs include

wordprocessorsfor creating and editing texts, spreadsheetsfor calculating mathematical formulae

and databasesfor storing data in a way that allows the data to be sorted and searched. Anti-virus

programsare used to detect and remove viruses(harmfulprograms that can reproduce themselves

and attach themselves to other programs). Some operating systems have graphical (user) interfaces

that allow the computer user to select items from menus(lists of choices) and to start programs using

an input device called a mouse. This is done by pressing a button on the mouse i.e. clickingthe

mouse. The main device for inputting the data is a typewriter-style keyboardand the output is

commonly displayed on a monitorscreen that looks like a small television screen.

There is a range of sizes and types of computer. Those designed for use by one person at a time are

known as personal computers (PCs)although the term PC is usually only applied to personal

computers that are compatible with the standards laid down by the company known as IBM

(International Business Machines). Personal computers include desktopcomputers (for use on an office

desk) and handheldcomputers that can be carried around by the user. Electronics can be added to

desktop computers by plugging in expansion cards(electronic circuit boards that can be plugged into

special sockets called expansion slots).

It is also possible to build all the main parts of a computer into one electronic integrated circuit

packaged as a single electronic chip(the common name for a microchip; an electronic integrated circuit

in a small package) i.e. the 'computer on a chip'. This enables computers to be built into other devices

including household devicessuch as washing machines and fridges and to be incorporated into plastic

cards i.e. smart cards, which are able to store information such as health records, drivers' licences,

bank balances, etc. Devices that include a computer circuit are commonly referred to as smart devices.

A multimedia computercan process different forms of data including text, graphics, audio(sound),

animation and video. This enables computer systems to be used for a combination of educationand

entertainment, sometimes referred to as edutainment.

Unlike most machines, computers do not have a fixed purpose. They are multi-purpose tools. They

can be used in a very wide variety of situations and are found in a wide range of systems including

security systems, cars and phones. Advanced systems, known as expert systems, enable computers to

'think' like experts. Medical expert systems, for example, can help doctors diagnose an illness and

decide on the best treatment. As computer systems are developed, they are becoming more common

and are gradually being used for more and more purposes. How they are developed, and for what

purposes they are actually used in the future, can be influencedby computer users. A variety of

devices known as peripheralscan be added externally to a computer. One of the most common

peripherals is a printerused for printing the computer output(the processed data or signals that come

out of a computer system) on paper. A digital cameraallows photographs to be input to a computer for

editing.

Not all computer systems are compatiblei.e. they cannot use the same programs and data.

Connecting computers together to form a networkcan provide the 'connectivity' required to enable

computers and software to communicate and to share resources. Networks connected together form

an internet. The connection of networks throughout the world is known as the Internet(note that a

capital I is used) or, more simply, the Net. Various communication services are available on the Internet,

including email(electronic mail) for sending and receiving text messages and IRC(Internet Relay Chat)

which allows users to communicate using text messages in real-timei.e. without any delay, while the

users are logged on(connected to a network system account, normally using a password) to the

system. An Internet service called FTP(File Transfer Protocol) is used for transferring data or program

files between the powerful servercomputers that provide the network services and the clientcomputers

that use these services e.g. downloading music files. Note that copying data from a larger server system

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to a client is referred to as downloadingand copying from the client to the server is known as

uploading.

One of the newest and most popular services available on the Internet is the World Wide Web

(WWW) which is often simply referred to as the Web (note the use of the capital W). The Web contains

interlinked documents called webpages. A set of related webpages stored together on a server

computer is called a website. Websites, such as Dogpile and Askjeeves, give the user access to

special programs called search enginesthat are designed to allow the user to find relevant webpages

on the Web. An Internet system designed to provide free, interactive access to vast resources for

people all over the world is sometimes referred to as an information superhighway.

Services such as these allow people to telecommute(use their computers to stay in touch with the

office while they are working at home). Computer uses mentioned in this unit include producing

greetings cards; learning, using three-dimensional graphics programs called 'Splat the Cat' and 'Pets 3';

using the Microsoft Word wordprocessing program including features such as clipart(ready-drawn

graphic images that can be inserted into documents); communicating on the Internet using email and

chat programs including the use of email attachments(other types of files e.g. video files attached to

simple email text messages); distance learning and videoconferencing(a form of communication over

a network that uses video cameras so that the people taking part can see and hear each other);

electronic classrooms or boardrooms; browsingthe Web (moving from webpage to webpage using a

Web browser program); selling, using a website; painting; scanning pictures; downloading music and

creating CD-ROMs (compact disk read only memory, commonly referred to as CDs). CD-ROMs are

storage devices that use laser light for reading and writing data. The most common storage device is a

hard disk(a set of aluminium disks coated in a magnetic material and enclosed in a vacuum-sealed

case) used for storing the operating system and applications programs as well as the user's data.

Date: 2015-12-17; view: 1380