Aleta Chuko Secondary And Preparatory School For Grade 9th TI Notes 2016

UNIT ONE
ORGANIZATION OF FILES

 This unit introduces you to files and file organization in computer systems.
 A computer file can be both system generated and created or transferred from other sources in to
a computer.
 You will learn how to manipulate files (creating, copying, renaming, deleting and searching).
 A file folder is a mechanism to keep your computer files in an organized manner.
 This unit will deal with folder manipulation mechanisms that operating systems provide.
 Files
 A file is a collection of data stored in one unit, identified by a filename. It can be a Word,
Spreadsheet, PowerPoint Presentation document.
 Files are represented by an icon in a computer.
 Thus, icons are small graphical representation of a file.
 A file stores a data which can be a document, a picture, text, video, audio, etc.
 A file has different icons in a computer.
 Folders
 Folder is Like A Container
 A folder, also called a directory, is a container which is used to store related files together.
 A folder can also contain another folder inside.
 A folder contained in another folder is called a subfolder.
 A good analogy is the manila folders (dossier) seen in an office to store papers or reports.
 The difference between a file and
 A folder is that a file is a collection or group of interrelated data and information whereas a
folder is a container used to store different files and subfolders.
 We can have different types of Files such as text, video, document and image and each has
different extensions.
 Importance of Folders
 Folders help to keep related files organized.
 This helps to locate files easily. If you had no folders on your computer, your documents,
programs and operating system files would all be located in the same place.
 Folders allow you to have more than one file with the same file name.
 Using File Explorer
 A file explorer (which was called Window explorer in applications before Window 10 version)

Element File Explorer Description and Usage

Numbers Elements
1 Navigation pane Navigation pane allows you to view and access
your computer’s file and folder structure. On
Navigation pane, there is a Quick Access area.
2 Forward and Back Enables you to go to folders you have previously
buttons opened. If you go to a different folder, you can
choose the Back button to return to the last
folder you accessed.
3 Ribbon Enables you to perform layout, formatting and
sharing tasks. It also enables you to change your
files’ and folders’ displays. Tasks available to you
might differ depending on what folder you select
(e.g. Documents versus Pictures).
4 Address bar Enables you to go to a different folder in the same

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Explorer window.
5 Column headings Titles of each of the columns displayed in the file
and folder list.
6 Search box Allows you to search for subfolders, documents,
images, programs, web pages and bookmarks in the
current folder.
7 File and folder listing Shows you the files and folders in the current folder
(the folder you selected in the Navigation pane).
8 Preview/Details pane Enables you to quickly preview an item, such as a
photo, without having to open that item.
9 Status bar Displays information about a selected folder
and its contents such as the total number of
items in the folder, the number of items selected
and the total file size.

Opening File Explorer

 To open File Explorer, click on the File Explorer icon located in the taskbar.
 Alternatively, you can open File Explorer by clicking on the Start button and then clicking on
File Explorer.

Creating New File

 A file is created using a computer software program. For example, to create a plain text file you
can use a text editor such as Notepad or Notepad++.
 You can use word processing software such as WordPad, Microsoft Word and LibreOffice
Writer to create a text document file.
 An image file can be created using image editing software such as Microsoft Paint, Paint 3D,
Gimp and Adobe Photoshop.
Saving the document
 Save allows you to update a previously saved file with new content, whereas Save As allows you to
save a new file or an existing file to a new location with the same or different name.
How to create a text file
 A text file is considered as a plaintext file and Notepad is capable of creating and editing plaintext
files. Notepad saves any text file with .txt file extension, which means no special formatting or
fonts.
Viewing, editing, and creating images
 There are many software programs you can use to display, view, edit and create images, logos or
arts on your computer.
 Microsoft Paint is a default image editing application software in window Operating system. We
can use it to simply edit our image file.
Creating presentation file
 Presentation files are created for electronic presentations consisting of a series of separate pages
or slides. To create presentation files, there are different application software such as Microsoft
PowerPoint and LibreOffice.

Creating a New Folder

 Creating a new folder can help you store related files in an organized manner.

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Copying a File
 Copying a file is used to put the file in a duplicated manner In Keyboard (Ctrl + C)
 To copy computer documents, pictures or other files from one place to another, follow the
following instructions.
 When copying files, you are going to get more than one copy of the file on your computer.
 If you want only one copy of the files, move them instead. A file name must be unique; otherwise,
a number will be appended to the end of a file name. It may also have “- Copy” appended to the
end of the file name, instead of a number.
 Appending a number to the end of the copied file’s name assures the copied file is unique.
 For example, if the original file name is StudentMarkList.pdf and a copy is created in the same
directory or folder, the copied file name could be Student Mark List (1).PDF or Student Mark
List - Copy. PDF.
Renaming File and Folder
 You must have right or permissions to a file, a folder or a directory to rename it. In some cases,
you may need administrator privileges in the operating system to rename.
 In Window, to rename files such as text, photo, document, audio and video files and folders, you
can use one of the following methods.
Method one
1. Highlight the file or the folder.
2. Right click the file with your mouse and select Rename from the menu that appears.

Method two

1. Highlight the file or the folder.

2. Press the F2 key on the keyboard.

Method three

1. Highlight the file or the folder.

2. Click File at the top of the window and select Rename from the list of available options.
Method four
1. Highlight the file or the folder you want to rename by single-clicking the file.
2. Once highlighted, wait a few seconds and click the file name again. A box should appear
surrounding the file or folder name, and you can rename the file.
 If you do not wait long enough and click the file or folder too fast, it can open the file or folder
rather than allowing you to rename it.
Accessing Files and Folders

There are a number of ways you can navigate to your files and folders in File Explorer. The
methods below will help you to do so.

 Using the Address bar (located at the top of File Explorer). The Address bar shows the full path
of your current location.
 Forward and Backward buttons
 From the Folders/Navigation pane
 Using the Search function (which searches file names and file and folder contents in the current
folder to find items containing your search term)
Displaying Subfolders Using Navigation/Folder Pane

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 The Folders pane or the Navigation pane is found along the left edge of every folder and displays
a directory tree of all the folders on your computer.
 You can select one or more folders in the Folders pane to display their contents in the File List
pane. The Folder/Navigation pane contains several main sections: Quick Access, One Drive, This
PC and Network.
 If you used previous versions of Windows 10, you know that a folder name would have a plus sign
next to it if that folder contains documents or subfolders.

With Windows 10, if a folder contains subfolders, that folder’s name will have a small right-
pointing triangle next to it (>).
 No triangle next to a folder name (Window 10) means the folder has no sub
folders.
 Right-pointing triangle next to a folder name (Network) means the folder has
subfolders.
 Down-pointing triangle next to a folder name (This PC) means the subfolders
are currently displayed for that folder.
 Moving Files and Folders on Computer
o There are several methods available to move computer files and folders (directories) from
one source or level to another.
o When moving files or folders, only one copy of the files is moved. If more than one copy of
the files is needed, copy the files and instead of move them.
 In Windows, you can move files using several methods. These are:
Cut and paste
Drag-and-drop
Use the “Move to Folder” command
Cut and paste
 To move files using cut and paste you can also use shortcut keys to cut and paste files.
 Select the files you want to cut, then press the shortcut key Ctrl+X to cut the files.
 Cutting the files is like cutting text in a document, i.e.
 It moves the files to a temporary clipboard until you paste them somewhere.
 Navigate to the destination folder and press the shortcut key Ctrl+V to paste the files.
 The files are now in your destination folder.
Drag-and-drop
 For drag-and-drop to work, you will need to be able to see the window of where you are
moving the files.
Move to Folder
o To move the files and folders using Move to Folder command.
 Deleting File and Folder
Now and then, it is a good idea to clean up your drives and delete duplicated files such as photos,
documents, temporary files and videos, and other unneeded or unwanted files and folders.
Users not familiar with Windows should realize that if they delete a folder or directory, all files
and folders in that folder or directory are deleted. Deleted files or folders can be restored from
Recycle Bin if not permanently deleted using shift + Delete key.
You can delete multiple files or folders by holding down the Ctrl key and clicking each file or
folder before pressing Delete.
You can hold down the Shift key while pressing the Delete key (shift + Delete) to delete the files
permanently.
In this case, restoring from Recycle Bin is not possible since the file will not go to the Recycle Bin
when deleted.

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You can delete multiple files or folders by holding down the Ctrl key and clicking each file or
folder before pressing Delete. You can hold down the Shift key while pressing the Delete key
(shift + Delete) to delete the files permanently. In this case, restoring from Recycle Bin is not
possible since the file will not go to the Recycle Bin when deleted. It will be deleted permanently.
Searching a File on a Computer
 All major operating systems running on computers can find files on the hard drive or other
drives connected to the computer.
 Microsoft Windows has a search feature that helps you find any file such as document,
spreadsheet, picture or video on your computer.
 To find a file, it is not required to know its full name.
 To find a file on a specific drive, click the drive under Computer or This PC in the left navigation
pane.
 Then enter the file name you want to search for in the Search field.
 File Explorer enables you to create, view, rename, delete and search files and folders in
computer.

To find a file on a specific drive, click the drive under Computer or This PC in the left navigation
pane. Then enter the file name you want to search for in the Search field.
Computer Drives
A Drive is a computer hardware component used to store and retrieve data, files, programs,
operating system, etc.
All drives store files and programs used by a computer. For example, when you write a letter in
a word processor, the program is loaded from the hard drive.
When you save the document, it is saved to the hard drive or other disk or drive.
In window operating system, a drive is often referred to by its letter like C:, D: or F:. However,
Linux operating system uses tree structure starting from root represented by forward slash (/).
For example, / home in Linux is a directory used to store users files.
A computer drive can be a hard disk drive, CD/DVD drive, removable disk (USB) flash drive, etc.
A hard disk drive (hard disk or fixed disk) is usually designated as the “C: drive”. The hard disk
drive is the main data and program storage hardware device that can provide quick access to
large amounts of data and program in a computer.
A CD/DVD drive, which is also called optical disc drive, allows you to use CD and DVD to listen
to music, watch movie or store any files.
It is usually designated as the “D: or G: drive”.
A USB drive, which is also referred to as a flash drive or memory stick, is a small, portable
device that plugs into the USB port on your computer.
USB drives are commonly used for storage, data backup and transferring files between devices.
Some users may be confused with “drive” and “Driver.” These are separate terms. The word
drive typically refers to a mechanical hard drive or solid-state hard drive used to store the
operating system, Data and programs. A driver is software code that enables one or more
hardware devices to communicate with the computer’s operating system. Without drivers, a
computer could not send and receive data correctly to hardware devices such as printer and
flash drive.

Accessing all drives available on a computer In Windows 10, it is possible to view all
mounted or attached drives in File Explorer. To achieve this, follow the following steps carefully.
1. Open File Explorer by pressing Windows key + E.
2. In the left pane, select This PC.
3. All drives are shown on the right.

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In Windows, most of your programs are stored in the Program Files folder, and your documents are
frequently saved in the My Documents folder.
✍ Drive is a hardware component of a computer which stores files and folders.
✍ Drive can be fixed and removable.
✍ Fixed drives are found within a computer while removable drives are portable and plugged
externally.
✍ This PC section of Window Explorer navigation part contains all drives mounted on the
computer.

UNIT TWO
COMPUTER NETWORK
Definition of Network

 A Network Is A Connection Of Two Or More Computers That Are Linked Together In Order To
Share Resources (Such As Printers, Files And Disks) Or Allow Electronic Communications.
 Using Bluetooth Application In Your Mobile Phone To Share Files Is An Example Of A Network.
 Sometimes, The Internet Is Called The Largest Global Network.
 The Figure Shows That The Laptop, The Tablet, The Mobile Phone And The Television Are
Connected To The Central Network Device.
 The Central Network Device Is, In Turn, Connected With A Global Network Through An
Internet Service Provider (ISP) Company Such As Ethiotelecom. You Will Learn More About
These In The Next Sections.

Fundamental Elements of Network

 Networks Are Comprised Of Four Basic Elements: Hardware, Network Software, Protocols And
Connection Medium.
 All Data Networks Are Comprised Of These Four Elements, And Cannot Function Without
Them.
 The Backbone Of Any Network Is The Hardware That Runs It.
 Network Software Is Also A Foundational Element For Any Network.
 This Type Of Software Helps To Manage Connected End Devices And Services The Network
Provides.
 Protocols Are Set Of Rules To Facilitate Electronic Communication Across Connected Device.
 Transmission Medium Which Can Be Wired Or Wireless, Caries Message Between End Devices.
End Devices

End Devices, Which Are Also Called Hosts, Are Devices Used To Send Or Receive Data Over The
Network. The Sending Device Is Called A Sender And The Receiving One Is A Receiver. Some
Examples Of End Devices Are:

 Computers (Such As Desktops, Laptops, File Servers And Web Servers Etc.)
 Network Printers
 Security Cameras

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 Mobile Handheld Devices.

Intermediary devices

 Intermediary Devices Interconnect End Devices.

 These Devices Interconnect And Work Behind The Scenes To Ensure Data Flow Across The
Network And The Devices.
 Intermediary Devices Connect The Individual Hosts To The Network And Also Can Connect
Multiple Individual Networks To Form An Internetwork.
 Intermediary Device Includes Network Cards, Routers Or Network Switches, Wireless Access
Point (WAP) And Repeaters.
Without these hardware devices, end devices have no means of accessing a network.
A. Network Interface Card (NIC)
 Is A Computer Hardware Component That Connects A Computer To A Computer Network.
 Card (NIC) Comes In A Card Form To Be Plugged Into The Computer System Or Can Be An
Integrated One As Part Of The Systems Board That You Often See In Laptops.
 NIC Has A Slot To Plug-In A Cable Connection With A Network.
B. Repeater
 Communication Media Or Cables That You Are Going To Limitation. This Includes The
Electronic Signal They Carry Will Become Weak After Traveling A Long Distance.
C. Switch
 Is A Device That Interconnects Various Devices Such As Computers, Printers And Servers In A
Small Business Network.
 Switch Is More Intelligent Device Than Hub As It Can Segment A Computer Network Into
Smaller Parts. In Addition, Switch Forwards Packets To Specific Destination After Learning
The Network Topology.
D. Router
 Consider Yourself As A Taxi Driver In A Given Town Which Has A Lot Or Streets (Roads)
Interconnected.
 Think About The Driver When He Or She Selects A Particular Street From Many Different
Options Available To Reach To His Or Her Destination.
 A Router Is Such An Intelligent Device Which Operates In Determination Of Pathways For
Electronic Messages In Networks.
 A Router, As Its Name Suggests, Works With Routing Or Finding A Route Through A Network.
That Is, It Is A Router Of A Network.
The Two Switches Are Connected To Each Other Through The Router. Assume Two
Different Cases.
Case 1: A Computer Sends A Message For Another Computer Within One Network; That
Is, Both The Sending And The Receiving Computers Are Connected To The Same Switch.

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Case 2: A Computer In One Network Segment Sending A Message To Another Network

Connected To A Different Switch.

Communication Protocol

 In Networking, A Protocol Is A Set Of Rules That Governs Data Communications.

 In Order For Different Network Hardware To Interact With The Network, They Should Follow
The Same Rules Called Protocols.
 It Is Software That Instructs Network Devices On How To Connect To The Network And How
To Interact With One Another.
 Internet Protocol (IP) Is One Of The Important Communication Protocols And Used For
Addressing Network Devices And Forwarding Data From One Network To Another.

Connection Media

 Without Physical Connections (Wired Or Wireless), A Network Cannot Function.

 The Connection Media Are The Media Which Are Used To Carry The Message From Sender To
Receiver.
We Have Two Types Of Communication Medium: Wired And Wireless.
I. Wired Medium: It Is Also Called Guided Medium. It Is A Cable That Connects End
Devices. Copper And Fiber Optic Cables Are Examples Of Wired Medium. The Most
Common Copper Cable Used In Networks Today Is Unshielded Twisted-Pair Cable (UTP),
Which Uses Electric Signal To Transmit Message For A Maximum Distance Of 100 Meters.
Fiber Optic Cable Uses Light To Transmit Signal At Faster Speed And Longer Distance
Than Copper Cable.
II.Wireless Medium: It Is Also Referred To As Unguided Media Or Unbounded Transmission
Media. It Is Used To Communicate Information Through The Air, Water Or Vacuum, E.G.
Radio Waves, Micro Waves, Infrared Waves And Satellite Communications.

Types of Networks
There Are Different Types Of Network Classified Based On The Following Four Categories:

 Network Media
 Size Of The Network Or Geographical Coverage Of The Network
 Topology
 Resource Security And Access

Types of Network Based on Connection Medium

Based on connection medium, computer networks are classified into wired and wireless networks.
Wired Network (ሽቦ)

 Wired networks, also called Ethernet networks, are the most common type of local area network
(LAN) technology.
 A wired network is simply a collection of two or more computers, printers, and other devices
linked by Ethernet cables.

Wireless Network (ሽቦ የሌለው)

 Wireless Networks Have No Physical Connection With The Wired Network; Instead They Get
Connected Through The Wireless Access Point (WAP).
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 A Wireless Network, Which Uses High-Frequency Radio Waves Rather Than Wires To
Communicate Between Nodes, Is Another Option For Home Or Business Networking.
 Individuals And Organizations Can Use This Option To Expand Their Existing Wired Network
Or To Go Completely Wireless.
 Wireless Network Allows For Devices To Be Shared Without Networking Cable Which Increases
Mobility.

Types of Networks Based on Size

Computer Networks Can Be Characterized By Their Sizes. The Size Of A Network Can Be
Expressed In Terms Of The Geographic Area The Network Occupies And The Number Of
Computers Connected To The Network. Networks Can Cover Anything From A Handful Of
Devices Within A Single Room To Millions Of Devices Spread Across The Entire Globe.
Some Of The Network Types Based On Size Are:

 Personal Area Network Or PAN

 Local Area Network Or LAN
 Metropolitan Area Network Or MAN
 Wide Area Network Or WAN

Personal Area Network (PAN)

 A Personal Area Network (PAN) Is A Computer Network Organized Around An Individual

Person Within A Single Building.
 A Common Example Is A Wireless Network That Connects A Computer With Its Peripherals.
 Almost Every Computer Has An Attached Monitor, Keyboard, Mouse And Printer.
 If There Is No Wireless Network, This Connection Must Be Done With Cables.
 A network created by Bluetooth is PAN.
 Bluetooth Is A Short-Range Wireless Network Used To Connect Computer’s Peripheral
Components Without Wires.
This Type Of Network Provides A Great Flexibility. For Example, It Allows You To:
 Send A Document To The Printer In The Office While You Are Sitting On The Couch
With Your Laptop.
 Upload A Photo From Your Cell Phone To Your Desktop Computer.
 Watch Movies From An Online Streaming Service To Your TV.

Local Area Network (LAN)

 LAN Is Generally An Organizational Or A Privately Owned Network Within A Single Office,

Building Or Campus Covering A Distance Of A Few Kilometers.
 The Main Reason For Designing A LAN Is To Share Resources Such As Storage Spaces,
Printers, Programs And Data.
 It Also Enables The Exchange Of Information.
 The Smallest LAN May Use Only Two Computers While Larger LANs Can Accommodate
Thousands Of Computers.
 A LAN Typically Relies Mostly On Wired Connections For Increased Speed And Security, But
Wireless Connections Can Also Be Part Of A LAN.
 If A LAN Is Entirely Wireless, It Is Referred To As A Wireless Local Area Network (WLAN).

Metropolitan Area Network (MAN)

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 A MAN Is A Network That Is Designed To Cover An Entire City.

 Suppose A Bank Wants To Connect Three Of Its Branches In A Given City.
 In Such A Case, The Bank Will Utilize The Service Of Existing Telephone Network Of The
City (For Example The Ethio-Telecom Network)
 To Interconnect Its Offices, Through Which MAN Is Created.

Wide Area Network (WAN)

 WAN Is Occupies A Very Large Area Such As An Entire Country Or The Entire World.
 A WAN Can Contain Multiple Smaller Networks Such As LANs or MANs.
 The Internet Is The Best-Known Example Of A Public WAN.
Types of Network Based on Topologies

Network Topology Defines How Various Computers Or Electronic Devices Represented As

Nodes Are Connected To One Another In The Network. It Refers To The Physical Arrangement Of
Devices In A Network. Typical Network Configurations Include Bus Topology, Mesh Topology,
Star Topology, And Ring Topology. Network
Topology

Bus Mesh Star Ring

Topology Topology Topology Topology
A. In bus topology
 In Bus Topology, There Is A Long Cable Called Bus Which Acts As A Backbone For All
The Nodes .
 A Bus Topology Network Connects Each Computer Or Electronic Devised To A Backbone
Cable (Or Bus) Just Like A Water Pipe Interconnections.

 A Bus Is Easy To Install And Uses Less Cables Than Other Topologies. However, Fault
Isolation Becomes Very Difficult In Bus Topology.
 It Is Also Relatively Difficult To Add New Nodes To A Bus, Thus Making It More Inflexible.
 This Is Because Addition Of A Node Changes The Number Of Taps And The Average
 Distance Between Them, Which Are Generally Optimized For A Bus Length.

B. Mesh Topology
 In Mesh Topology (Also Called Complete Topology), Each Node Is Connected To Every
Other Node By Direct Links. Illustrates This.
 Mesh Topology Does Not Have Traffic Congestion Problems Due To Dedicated Links.
 This Topology Has The Advantage In Terms Of Data Security.
 It Is Also Robust; That Means, If One Link Is Down, The Rest Of The Network Can Still
Continue. Fault Identification Is Also Easy In This Case.
 The Main Demerit Of This Network Scheme Is Cable Length And Consequent Cost And
Complexity. This Is Clearly Impractical For Medium To Large Networks.
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C. Star Topology
 In A Star Topology, Each Device Has A Dedicated Point-To-Point Link Only To A Central
Controller, Usually Called A Switch.
 The Devices Are Not Directly Linked To One Another. Unlike A Mesh Topology, A Star
Topology Does Not Allow Direct Traffic Between Devices.
 If A Node Wants To Send Some Data To Another Node, It Sends It To This Switch.
 Star Topology Is Cheaper Than Mesh Topology.
 It Is Also Relatively Easier To Install, Maintain And Reconfigure.
 It Is Also Robust. However, If The Switch Goes Down, The Entire Network Becomes
Defunct.
 This Is A Major Demerit Of This Scheme.

D. Ring Topology
 In Ring Topology, Each Node Is Directly Connected To Only Its Two Adjacent Neighbors.
 If A Node Wants To Send Something To A Distant Node On A Ring, It Has To Go Through
Many Intermediate Nodes, Which Act Like Repeaters, Reproducing The Incoming Bit
Stream With Full Signals On The Outgoing Line.
 A ring is easy to reconfigure and install. In a ring, a signal normally circulates all the time.
 A node not receiving any signal for a long time indicates a fault. Therefore, fault isolation is
relatively easy in a ring.
 However, if a node in a simple ring fails, the whole ring cannot function. Another demerit is
that traffic flows only in one direction.
 This topology is not used if the number of nodes to be connected is very high.

Advantages And Disadvantages Of All Network Topologies

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Topologies Advantages Disadvantages

- Cheap - Difficult To Reconfigure
Bus Topology - Easy To Install - Break In Bus Disables
Entire Net Work
- Cheap
- Easy To Install
Mesh Topology - Easy To Reconfigure - More Expensive Than Bus
- Fault Tolerant

- Efficient
Star Topology - Easy To Install - Reconfiguration is difficult
- Very expensive
- Simplest - Extremely difficult for
Ring Topology - Most Fault Tolerant reconfiguration
- Extremely expensive
- Very complex

Types of Network Based on Resource Security and Access

Peer-To-Peer Network

 In A Peer-To-Peer Network, Each Machine (Computer) Is Known As Peer And Can

Participate In The Sharing Of Files Or Resources.
 No Server Is Required In This Network, So There Is No Additional Cost For A Dedicated
Machine, But There Is Also No A Real Security.
 A Peer-To-Peer Network Is Also Called Workgroup And There Is No Hierarchy Among The
Computers.
 This Mean That All Computers Are Peers (Equals) And The Connection Is Created For
Resource Sharing And Communication Purposes Only.
 The Number Of Computers In Peer-To-Peer Network Usually Does Not Exceed 10; If The
Number Is Beyond This, The Network Becomes Very Difficult For Administration.
Advantages Of Peer-To-Peer Network
ƒ
 Server Is Not Required. ƒ
 All Computers Are Equal In The Network. ƒ
 No Additional Cost Is Needed For Dedicated-Machine.

Disadvantages Of Peer-To-Peer Network ƒ

 Provides Share Level Security, I.E. It Applies A Trust-Based Security. ƒ

 Can Work In Small Environments Only.

Client-Server Network

 A client is a computer which requests resources and services while a server is a computer
which provides services and resources according to client requests. Informally, clients often
tend to be desktop PC’s or workstations, while servers are more powerful machines.
 A Client-Server Network Involves Multiple Clients Or Workstations, Connecting To At Least
One Central Server. Most Resources Are Installed On The Server.
 When Clients Need Access To These Resources, They Access Them From The Server.

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 Servers Often Have Private User Directories As Well As Multiple Public Directories.
 In Client-Server Networks The Clients Are Allowed To Function As Workstations Without
Sharing Any Resources.
 It Is Easier To Upgrade Software Applications And Files Because They Are Held On One
Single Computer.
 System-Wide Services Can Be Provided Through The Server Software.
 Security Is Enhanced On A Client Server Network Because The Security Is Handled By The
Server.

Advantages Of Network
There Are More Advantages To A Network Than Disadvantages. In Fact, Many Companies Today
Would Not Exist Without Accessing Some Form Of Network. Below Are The Advantages Of A
Network. ƒ

 Sharing Data And Information - One Of The Biggest Advantages Of A Network Is

Sharing Data And Information Between Each Of The Devices On The Network. In Addition,
Networks Allow Accessing The Data Which Is Stored On Central Computer Called Database
Server. For Example, We Use Network For Sharing Documents, Images, Photos, Songs And
Videos. ƒ
 Communication - A Network Gives All Users The Ability To Quickly Communicate With
Each Other Either Using Chatting Or Instant Messaging Services Such As Skype, Whatsapp
And Viber To Send Files And Messages Among The Users, Video Conferencing, E-Mail, TV
And Radio.
 Sharing Hardware – Expensive Hardware Devices Connected To A Network Can Be
Shared Among All Users. ƒ
o Storage Devices Such As Hard Disk That Are Shared On A Storage Server, Which
Is Also Called NAS (Network Attached Storage), Can Store And Access Vast Amounts
Of Information. ƒ
o A Printer Which Is Attached And Shared On A Server (Printer Server) Allows All
Network Users To Print From One Printer According To Their Privilege Configured
On The Server By A Network Administrator. ƒ
o Fax Machines, Scanners, More Powerful Computers, Such As Super Computers
That Can Perform Complex Tasks Within Short Period Of Time Than A Single
Computer Will Take To Complete. ƒ
 Share Software – Different Application Software And Internet-Based Services Can Be
Shared Over The Network For All Licensed Users For The Software. For Instance, We Can
Share Software Such As Computer Games And Work Internet-Based Services Such As E-
Learning. E-Learning Or Learning Management System In Its Broadest Sense Is Designed
To Support teaching and learning as well as student-to-student and student-to teacher
instructions. ƒ
 Transferring money - Being connected to a secure network allows a person or business to
digitally transfer money between banks and users. For example, a network could allow a
company not only to manage employees’ payroll but also to transfer their pay to the
employee’s bank account.

Disadvantages of network
Although there are many advantages to a network (mentioned above), there are some
disadvantages. Below are some disadvantages of a network. ƒ

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Aleta Chuko Secondary And Preparatory School For Grade 9th TI Notes 2016

 Virus and malware - Networks make sharing information between network users easy.
Unfortunately, this also means that viruses and other malwares have an easier time
spreading between computers on a network. ƒ
 Vulnerabilities - When computer are connected on the network, it will be accessible
remotely, with these potential new methods of accessing the computer; it can introduce new
security issues or vulnerabilities to the computer, users and the data on the network which
affect the organization and the country at large. ƒ
 Complex - Networks are complex, and setting up and managing a network for a business or
corporation requires someone with a lot of experience or certification. ƒ
 Cost - Setting up, managing and administering a network hardware and software incurs
cost to the organization building a network. ƒ
 Social media effect on youth and adults - particularly youths, including students, waste
their time on use of social media and unsafe Internet resources. There are also many cyber
security threats such as cyber bullying, disinformation/misinformation and identity theft that
you should be aware of and learn to develop safe use of the Internet.

UNIT THREE
APPLICATION SOFTWARE
Using Application Software
The Software Used By General Public Users In Their Daily Tasks Most Often Is Application
Software. Some Examples Of Application Software Are: ƒ

 Word Processing Software ƒ

 Presentation Software ƒ
 Spreadsheet Software
 Application Software May Consist Of A Single Program, Such As Microsoft Notepad, For
Writing And Editing Simple Text.
 It May Also Consist Of A Collection Of Programs Called A Software Package, Which Work
Together To Accomplish A Task.
 Application Software May Also Include A Larger Collection Of Programs (A Software
Suite), Related But Independent Programs, Which Have A Common User Interface Such As
Microsoft Office Suite.
Word Processing
 Word Processing Refers To The Act Of Using A Computer To Create, Edit, Save And Print
Documents Including, But Not Limited To, Textual Reports, Letters, Memos, Newsletters And
Brochures.
 In Order To Perform Word Processing, Specialized software (known as a Word Processor) is
needed.

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