Information Technology Ms. Abeer Helwa

Information Technology Ms. Abeer Helwa

Software

SoftwareThey are instructions that tell the computer what to

do and how to do it.

Software

Operating System ApplicationSoftware

1) Operating systemAn interface between hardware and user, which is

responsible for the management of activities and the sharing of the resources of a computer.

Examples of operating system:MS DOS (Disk Operating System)MS Windows (98 – Me – 2000 – XP – Vista – 7).MAC OS.UNIX.

Operating system Typesa. CLI (Command Line Interface):A user interface in which you type commands

instead of choosing them from a menu or selecting an icon.

Operating system Typesb. GUI (Graphical User Interface):A visual way of interacting with a computer using

items such as windows, icons, and menus.It is user-friendly.

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Operating system TasksInterface: It provides an interface between the user and the

machine.

Resource management:Allocates computer resources such as CPU time,

main memory, secondary storage, and input and output devices for use.

Operating system TasksInput/output management: This checks the input and output of the data, their

location, storage, and retrieval.

File management: Setting up directories to organize your files

according to their type and displaying a list of files stored on a particular disk.

2) Application SoftwareSpecial software to do special functions.

Examples of ApplicationsWord Processor:It is used to write and format texts, insert tables

and pictures, e.g. MS Word.

Spreadsheet:It is used for automatic calculations and creating

charts, e.g. MS Excel.

Database:A structured set of data held in a computer, e.g.

MS Access.

Examples of ApplicationsWeb Browser:A program designed to enable users to access,

retrieve and view documents and other resources on the Internet, e.g. Internet Explorer.

Presentation:It is used to design slides for business and

education, e.g. MS PowerPoint.

Computer Networks

Network DefinitionIt is a set of tow or more connected computers to share resources.

Advantage of using NetworksInformation sharing.Resources sharing (printers).Software sharing.Information protection (user names and passwords)Emails.

Network Types

1) LAN.2) WAN.

1) LAN ( Local Area Network)It is a group of computers connected together in

the same region or limited area.

2) WAN (Wide Area Network)A network that connects computers over wide

geographical area or may be other countries using telephone lines or satellite.

Main Parts of network architecture

1) Client:It is a computer connected to the network and

hasn’t any control privilege.

2) Server:It is a computer that is responsible for controlling

network resources.

3) Resources:All files, printers and other hardware or software

that the network users can share.

Internet(Interconnected Network)

• It is a global network of inter-connected networks.

• A system of connected computers that allows your computer to exchange data, messages and files with any of the millions of other connected computers.

Intranet(Internal Network)

An Intranet is a network of computers within a private company.

It is a close version of the Internet but can only be accessed by authorized members in the same organization.

Extranet(External Network)

It is similar to an Intranet but it can be accessed by outsiders who have the permission to access the company’s network.

Note:

• All of these networks need a modem to work.• The speed of modem called Transfer rate

and it is measured by bps (bit per second).• New modem speed is measured in Mbps or

Gbps

Terms

WWW (World Wide Web):A collection of web pages and related

resources which are linked together across the internet.

ISP (Internet Service Provider)It is a company that provides individuals and

other companies access to the Internet, and other related services such as Web site building and virtual hosting.

TermsURL (Uniform Resource Locator)Every page has its own unique address.

Terms• Web Browsers:They are software application used for retrieving

and presenting an URL on the World Wide Web.

• Cookie A file created by an Internet site to store information

on your computer.

TermsWeb Site A computer Storage area that contains one or

more web pages.

Home PageThe first web page you see when you lunch

Internet Explorer.

TermsSearch EngineIs designed to search for information on the World

Wide Web.

TermsDownloading The process of transferring a file from a network

computer to a local computer.

Uploading The process of transferring a file from your local

computer to a network computer.