Step 1: Open the Search BarStep 2: Type 'excel' on the search bar, locate excel icon and select 'open'Other Excel Starting Options
Start button > Microsoft Office Folder > Microsoft Office Excel 2007
Search bar > Type 'Run' then tap (dialog box opens)> Type 'excel' > press enter key on the keyboard
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Quick Access Toolbar
Title BarMinimize, Restore and Close buttons![]()
Minimize button minimizes excel window as a button on the task bar, restore button reduces the size of the window vis a vis, close button exits excel window or document. Note that the upper buttons apply changes to the excel window and the lower buttons effect changes to the excel document (workbook).
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A rowScroll Bars (Horizontal and vertical)Worksheet Navigation (Control panel)Status bar![]()
A status bar is a graphical control element which poses an information area typically found at the window's bottom. It can be divided into sections to group information. Its job is primarily to display information about the current state of its window, although some status bars have extra functionality.
Zoom SliderTabbed PageviewColumn headerRow headerAll cells selectorExcel help tool (F1)
Introduction
Excel 2007 is a powerful spreadsheet application that allows users to produce tables containing calculations and graphs. These can range from simple formulae through to complex functions and mathematical models.
Our guidelines will cover the Microsoft 2007 Excel software given it's simplicity to learners and stability in performance. This regards to the KCSE and KICD Syllabus for the form 2 computer studies.
Objectives
Our practical sessions will seek to address the following:
4.2.0 SPREADSHEETS (18 LESSONS)4.2.1 Specific ObjectivesBy the end of the topic, the learner should be able to:
4.2.3 Definition of a Spreadsheet4.2.4 Components of a spreadsheet
4.2.5 Application areas of a spreadsheet
4.2.6 Creating a worksheet/workbook
Creating a worksheet
4.2.7 Cell Data Types
4.2.8 Cell referencing
4.2.9 Basic functions and Formulae
4.2.10 Worksheet formatting
4.2.11 Data Management
4.2.12 Charts/graphs
4.2.12 Printing
SPREADSHEETS.Definition of a Spreadsheet.
A Spreadsheet is a ledger sheet that lets the user enter, edit, and manipulate numerical data.
A Spreadsheet usually consists of a series of rows & columns in which data entries can be made. Types of Spreadsheets:
There are 2 types of spreadsheets:
1). Manual spreadsheet:
A Manual spreadsheet is ledger book with many sheets of papers divided into rows and columns for entering/writing data.
The data is entered manually using a pen or pencil. 2). Electronic Spreadsheet:
A computer program that looks like the manual ledger sheet with rows & columns for entering data that can be manipulated mathematically using of formulae.
Advantages of Electronic Spreadsheets over Manual Worksheets.
An electronic spreadsheet:
Examples of the commonly used Spreadsheet packages
Review Questions.
COMPONENTS OF A SPREADSHEETA spreadsheet has 3 main components, namely;
Workbook:
When working in any spreadsheet program, you use workbook files to hold your information. A Workbook is a file in a spreadsheet package that contains one or more worksheets. The worksheets are made up of rows & columns in which you work and store your data. A Workbook allows the user to organize various kinds of related information in a single file. Database:
Spreadsheet programs such as Excel have special features, which can be used to manage data values entered in the cells of the spreadsheet.
These features, which are found on the Data menu, were incorporated in Excel but they belong to Database Management System software. Examples of such features include: Filtering of records, use of Forms, calculating of Subtotals, data validation, Pivot tables and Pivot chart reports. Example:
If related data values are entered on the same row, they form a Record. Hence, a worksheet can be manipulated as a database that has data records entered in it.
Graphs/Charts:
A Chart is a graphical/pictorial representation of data in a worksheet. Charts are used to summarize data in a worksheet in a pictorial form. They enable the users to present complex data elements from a worksheet in a simple format that they can understand. Charts make it easy for users to see comparisons, patterns, and trends in data, e.g., instead of having to analyse several columns of a worksheet, one can see at a glance whether sales are falling or rising. Examples of charts are: Pie charts, Line graphs, Bar charts, Histograms, Column charts, etc. Review Questions.
Application areas of spreadsheets (Areas where Spreadsheets are used)1. Accounting.
Spreadsheets provide an easy & streamlined means of financial management. They are mostly used by Accountants to record their daily transactions & also keep financial records.
For example; a spreadsheet can be used to do the following:
2. Data management.
A spreadsheet enables information to be produced easily and kept up-to-date.
For example;
3. Scientific Applications.
Spreadsheet programs can be used by Scientists & Researchers to compile & analyse their results.
4. Statistical analysis / Mathematical operations.
Spreadsheets provide a set of data analysis tools that can be used to develop complex statistical analyses. In addition, some of the tools generate charts.
Examples of statistical functions include:
5. Forecasting (What if analysis).
The automatic recalculation feature makes it possible to use the “What if” analysis technique.
What if analysis is a feature in a spreadsheet that is used to find out the effect of changing certain values in a worksheet on other cells. It involves changing the value of one of the arguments in a formula in order to see the difference the change would make on the result of the calculation. This method can be used for financial forecasting, budgeting, cost analysis, etc. Review Questions.
Common features of Electronic spreadsheets.
The following are the typical facilities provided by electronic spreadsheets: An electronic spreadsheet: -
Review Questions.
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NETWORK MODELSA Network model describes how the computer processes information on the network. Data can be processed by a Client, a central Server or by all the computers on the network. 1). Centralized computer model.Very large computers, usually mainframes, are connected with terminals. The users input & output data using the terminals, while the processing is done by the central computer (mainframe). Advantages of Centralized model
Disadvantages of Centralized model
2). Distributive computingIn this model, data is stored and processed on the local workstation. Computers acting as Stand alone systems are connected together for increased functionality.A Stand alone is a computer which is not connected to any other computer equipment other than its own Printer. Advantages of Distributive Computing model.
Disadvantages of Distributive Computing model.
3). Collaborative model.In this model, all computers can share processing power across the network. Applications can be written to use the processing on the computers to complete job more quickly. Advantages of Collaborative model.
Disadvantages of Collaborative model.
CATEGORIES OF NETWORKS1. Peer-to-Peer network.A Peer is a computer that acts both as the client and a server.In this network, all the connected computers are equal & each machine acts as both client and Server. This means that, there is no central storage area for information & no dedicated central Server. No system administrator. Therefore, the user of each computer determines what data & resources the computer will shares with other computers on the network. Peer-to-peer networks are appropriate in an environment where:
Advantages of Peer-to-peer networks.
Disadvantages of Peer-to-peer networks.
2. Server-based networks.In this network, there is usually a Server, e.g. a company which is dedicated to handle files and/or information for clients, make & service requests from network clients, and ensure security of files and directories for them. Server-based networks require a network operating system. Advantages of Server based networks.
Disadvantages of Server based networks.
Review questions.2. How does each of the following networking models operate?
Network SecurityIn networking, there are several ways of protecting your data and information from intruders. They include: Share level and User level security. Share level securityThis model of security is mostly used in peer-to-peer networks. The user can decide which resources to give for sharing. Most Windows operating systems such as Windows 9X provide such kind of security. User-level securityThe User level security is used on server-based networks. A network administrator assigns accounts to users, i.e., each user is provided with a unique name and a password which he/she can use to access network resources. Review questions.
COMMUNICATION OF DATA IN A NETWORK.Data in a network travels from one computer to the other using laid down rules known as Protocols. The protocols used depend on the way the computers are connected together on the network. Generally, there are 2 broad ways in which computers communicate with one another in a network, namely:
Point-to-point communication.In point-to-point, the network contains numerous cables or telephone lines, each one connecting a pair of computers. The message is received at each intermediate computer in whole, stored there until the required output line is free, and then forwarded. A network using this principle is called a point-to-point or store-and-forward network.
Broadcast communication.In broadcast, there is a single communication channel shared by all computers. In this case, the messages sent by any computer are received by all other computers. Something in the message itself must specify for whom it is intended. After receiving a message not intended for itself, a computer just ignores it. Review questions.
Network TopologiesThe term network Topology refers to the way in which computers, cables, and other devices have been arranged in the network. It can also refer to how data is passed from one computer to another in the network. Logical and physical topologiesNetwork topology can be viewed in 2 ways; Logical or Physical. Logical (Signal) topologyLogical topology deals with the way data passes from one device to the next on the network. Examples of logical topologies are:
Ethernet topologyIn Ethernet topology, all computers listen to the network media, and a particular computer can only send data when none of the others is sending. Token ring topology In Token ring topology, a special package for data called a token goes around the network. The computer whose address is on the data held in the token picks it up, reads the data, and then releases the token. The token can then be captured by another computer which needs to transmit data.
Physical topologyPhysical topology refers to the physical arrangement of components on the network. Examples of physical topologies are:
The choice of the topology to adopt depends on factors such as Reliability, Expandability, and Performance. Star topologyStar topology consists of computers and other devices, each connected to a common central server called the Hub. However, to connect to the central machine, each computer uses a separate cable. Nodes communicate across the network by passing data signals through the hub, i.e., any two computers (workstations) in the network communicate through the central machine. When the hub receives data from a transmitting computer, it broadcasts the message to all the other nodes on the network. Advantages of Star topology.
Disadvantages of Star topology.
Bus topology (Daisy-chain topology)In Bus topology, all the devices in the network are connected directly, through appropriate interfacing hardware, to a single transmission cable called the Bus (or Backbone) on which information is broadcast.
Bus topology uses Coaxial cable as transmission medium. The cable can carry only one message at a time and each workstation on the network must be able to know when it can and cannot transmit using this cable.
A Terminator is attached to each end of the cable to avoid signals from bouncing back and forth on the cable causing signal distortion. For communication to take place, data is addressed to a particular computer & put in the cable in the form of electronic signal. As the data passes along the cable, each workstation checks whether the data is addressed to it. If the address in the data matches that of the machine, it picks up the data and processes it. Bus topology doesn’t need any special equipment such as switches or repeaters to amplify the signal. Advantages of Bus topology.
Disadvantages of Bus topology.
Ring topologyIn a ring topology, the computers are connected to one another in the shape of a closed loop using a single cable.
Data flows from one computer to another in one direction, and each computer actively participates in data transfer from one station to the other. In other words, each workstation acts as a booster by regenerating and retransmitting the signals around the network to its neighbour.
A token is used to exchange data from one station to another. A token can be viewed as an envelope or a bag where data is placed for transmission and carried around the network. Advantages of Ring topology.
Disadvantages of Ring topology.
Mesh topologyMesh topology uses separate cables to connect each device to every other device on the network providing a straight communication path. It is mostly used in Wide Area Networks where there are many paths between different locations.
Advantages of Mesh topology.
Disadvantages of Mesh topology
Tree (Hierarchical) topologyThis is a hybrid topology where groups of star-configured networks are connected to a linear bus (backbone). Review questions.
Network softwareNetwork software can be classified into 2 main groups:
Network Operating systemsThese are operating systems specifically designed to enable the networked computers to respond to service requests. Servers run on a network operating system. Functions of network operating systems
A network operating system performs the following network related functions:
Network OS are normally designed as Multi-user operating systems that run the network server program. Examples of network operating systems are:
ProtocolsProtocols are a set of rules and procedures that govern the communication between two different devices or people. E.g., a diplomat from a foreign country must adhere to the set rules and procedures of communication when representing his country in the host country. In computer networking, Protocols are the rules and technical procedures that govern communication between the different computers on the network. How Protocols work
The Open Systems Interconnection (OSI) reference model.
Interconnecting of the various hardware & software products from different manufacturers together into a single network requires that the equipment must be able to communicate and work with each other.
The OSI reference model defines standard (uniform) methods which enable different systems to interoperate with each other and to be portable across one another. Network protocols are usually designed using the OSI reference model. To facilitate communication between application processes located on different computers, the model groups similar computer communication protocols into 7 layers, each performing specific functions. Protocols at the Application layer:They provide services to application programs such as the E-mail editor program that enables composing or reading of e-mail messages. Examples of protocols at the Application layer include:
Protocols at the Transport layer:They ensure that data is passed between computers more reliably. Examples of protocols at the Transport layer include:
Protocols at the Network layer:They provide link services, e.g., they handle addressing and routing information, error checking and retransmission of requests. Examples of protocols at the Network layer include:
Review questions.
Wireless communication devicesFor a long time, networks have been implemented using tangible transmission media like cables. However, since the cost of wireless technology has gone down & the quality of service increased, companies & individuals are now using wireless segments in their communications with the aim of extending the capability of wired networks. The most common devices (components) used in wireless communication are: Access Points (AP), and Wireless antennae. 1. Access points (AP)An Access point is an entry point into a bounded network.
It is used by people who have wireless devices such as Personal Digital Assistants (PDA’s), Laptops, and computers with wireless links. 2. Wireless antennaeThe Access point should have antennae so as to detect wave signals in the surrounding. The waves may be Radio waves, microwaves or infrared waves. Most Access points have 2 antennae so that the one that receives the best signal at any particular time can be used.
Personal Computer Memory Card International Association (PCMCIA) cardA PCMCIA is a card inserted into a device such as a Personal Digital Assistant (PDA) or a laptop in order to enable wireless communication between the device and a wired network server. Communication devicesFor a network to be fully operational, communication devices are required, and act as interfaces between the Terminal devices. Terminal equipments are the devices at both ends of the communication link, e.g., computers. Some of the data communication devices are: 1. Network Interface cards (NIC)
A NIC acts as a physical connection (link/interface) between the computer & a properly terminated transmission cable. A NIC is plugged into an empty expansion slot on the motherboard, and has ports at the back in which the terminated end of a network cable can be plugged. 2. A Modem and a CodecA Modem converts a digital signal to analogue form so that it can be transmitted over an analogue media. A Codec converts an analogue signal to digital form so that it can be transmitted over a digital medium. A modem can be external, an add-on card or built on the motherboard. 3. Hub (Concentrator)A Hub is a component that connects computers on a network, and is able to relay signals from one computer to another on the same network. A Hub usually connects networks that have the same set of communication software usually called Protocols.
A Hub transmits signals by broadcasting them to all the computers on the network. After the signal is broadcasted, the computer whose address is on the message then picks the message from the network.
Several hubs can be connected together one after another to expand a network. Intelligent hubsIntelligent hubs are able to monitor the way computers are communicating on the network, and keep the information in their own database called management information base (MIB). The network server can then use this information to fine-tune the network.
4. BridgesThis is a network device that selectively determines the appropriate network segment for which a message is meant to be delivered. It does this through address filtering. Purpose of using a Bridge
5. RepeaterA Repeater receives a signal from one segment of a network, cleans it to remove any distortion, boosts it, and then sends it to another segment. It therefore, enables the network to eliminate attenuation problems. Note. Repeaters can easily be used to expand a network. This is because; they broadcast the same message to other network segments.
6. RoutersA Router connects different networks, and directs the transfer of data packets from source to destination. Note. Routing depends on network addresses. Each network has a unique address (or identifier) called the IP address. The router will receive a packet of data from another router on the network, and check the network address of the destination. If the address is the same as the one on which the router is, the router will then read the address of the host and then pass the data packet to the destination, otherwise the packet will be routed to the next network address. NB: Network addressing has been made possible because of the use of a special interconnecting protocol called the Internet Protocol (IP). 7. GatewaysA Gateway is any device that can be configured to provide access to a Wide Area Network or the Internet. Note. A gateway may be a router, or a computer configured to provide access to the Internet. 8. SwitchesUnlike a hub, a Switch forwards a data packet directly to the terminal equipment on the network without broadcasting. It does this by connecting the two nodes point-to-point as if they were linked by a direct cable. Note. Some hubs can also act as switches. Such a hub is referred to as a switching hub.
Review questions.
Wireless communication (unbounded media)Wireless (unbounded) media is a type of media that is used to transmit data from one point to another without using physical connections. In this case, a transmitting antenna & a receiver aerial are used to facilitate the communication. Examples of wireless communication media include:
Microwave transmissionMicrowave frequencies have a small wavelength, and can easily release their energy in water as heat. This is why they are used in making domestic kitchen appliances, e.g., microwave ovens. In networking, microwaves are suitable for point-to-point transmissions, whereby a signal is directed through a focused beam from the transmitter to the receiver station. Satellite communicationA Satellite is a microwave relay station. The microwave earth stations have parabolic dishes with an antenna fixed on them in order to focus a narrow beam towards the satellite in space. A satellite transmission system has 3 main components:
A communication satellite is usually launched into space about 36,000 km above the earth in such a manner that its speed is almost equal to the rotation speed of the earth. This makes the satellite appear as if it is stationary in space. Such types of satellites are called geostationary satellites.
Advantages of using satellites
Very Small Aperture Terminal (VSAT)A VSAT is a very small satellite dish used both in data, radio, and TV communication. It can be set up at home or in a small business. It enables direct access to satellite communication instead of having to go through state-owned or licensed satellite gateways. The dish has an antenna that receives the satellite signals. The signals are decoded using a decoder which is plugged directly to a television set or a computer. Radio communicationRadio waves are used in radio and television broadcasts. Radio waves travel just like surface water waves, i.e., they start from a central point and spread outwards in all directions. As they travel outwards, their energy spreads outwards over the covered area. The waves are radiated into the atmosphere by a radio frequency antenna at constant velocity. The figure below shows a typical radio waves link between two separate geographical locations.
Radio waves can be of:
High frequency (HF) radio wavesThe High frequency radio wave signal is transmitted by directing it to the ionosphere of the earth. The ionosphere reflects it back to the earth’s surface, and the receiver then picks the signal. Disadvantage of HF communication
They are transmitted along the earth’s surface. However, since the earth is somehow curved, the signal tends to attenuate at the horizons of mountains and buildings. This means that, repeater stations have to be built on raised areas in order to receive, amplify, and propagate the signal from one area to another. Note. The range of VHF is limited, however, it is preferred to HF because; it is possible to make a VHF wave follow a narrower & more direct path to the receiver. Ultra-High frequency (UHF) radio wavesThe UHF radiowaves use the line of sight principle used by the VHF waves. This means that, there should be no barrier between the sending & the receiving aerial. However, they require smaller aerials. For example;The Television aerial for VHF is bigger than the one for UHF radio waves. This is because; UHF radio waves can be made to follow a narrower & a more direct path to the receiver than VHF radio waves. The Bluetooth technologyThis is a worldwide and short range radio transmission technology that allows all personal, hand-held devices to be able to communicate with each other through wireless technology. It enables people to use hand-held communication devices such as mobile phones & Personal Digital Assistants (PDA’s) to access the Internet. The main component in Bluetooth is a small low power two-way radio transceiver, which can be inserted in small devices. Bluetooth enabled devices use a network called the Wireless personal area network (WPAN) or piconet. Infrared transmissionCommunication through infrared waves (signals) is achieved by having infrared transmitters & receivers (transceivers) within a line of sight in the same room. This is because; infrared signals cannot penetrate obstacles like walls and ceilings. However, the signal can be reflected off these surfaces until they reach their destination. For example;Most mobile phones have an infrared transceiver. Once activated, two people in the same room can send messages to each other on their mobile phones without going through the mobile service provider; hence avoid being charged. In computer networking environment, infrared technology can be used to connect devices in the same room to each other without the need for cables, e.g., a computer and a printer. However, the computer’s infrared transceiver must maintain a line of sight with the one for the printer. Advantages of wireless communication.
Disadvantages of wireless communication.
Review questions.
Fibre optic cables.
A fibre optic cable uses light to transmit data signals from one point to another on the network. A Light Emitting Diode (LED) is used at the source/transmitter (sending computer) to convert electrical signals to light signals which are then send along the cable. At the receiving computer, a photosensitive device is then used to convert the light signals back to electric signals that can be processed by the computer. A fibre optic cable is made up of;
1. The Core.
This is the central part of the cable, and is made of a hollow transparent plastic or glass. 2. Cladding.
This is a single protective layer surrounding the core. The Cladding is able to bend light rays, (i.e., when light tries to travel from the core to the cladding, it is redirected back to the core). 3. Buffer.
It surrounds the cladding. Its main function is to strengthen the cable. 4. The Jacket.
Types of fibre optic cables.(i). Single mode fibre optic cable.
The single mode fibre has a very narrow centre core. This implies that, the light in the cable can take only one path through it.
(ii). Multimode fibre optic cable.A multimode fibre has a thicker centre core than the single mode fibre.
Advantages of fibre optic cable.
Disadvantages of fibre optic cable.
ELEMENTS (COMPONENTS) OF NETWORKINGA computer network is made up of several standard components, which can be classified into three (3) major categories, namely:
Data communication (Transmission) media.A data communication medium is a physical pathway used for carrying data signals & information from one point to another. Data communication media can be divided into two:
(a). Communication using cable (bound media). (b). Wireless communication (unbounded media).
Communication using cables (bounded media).In bounded media, data signals are transmitted from the source to the destination through a cable. There are 4 major types of bounded transmission media, namely:
Two-wire open lines cables.Two-wire open lines cables are made up of 2 parallel copper wires separated by a plastic insulator.
The Plastic insulator is meant to reduce signal interference called Crosstalk. However, the linear nature of the wires allows an electromagnetic field to build around them during heavy data transmission, which may cause interference to the signal.
The wires also capture/pick unwanted environmental frequencies, e.g., radio waves, hence causing noise in the transmission channel. Two-wire open lines cables are used in telecommunication network to transmit voice (analogue) signals. Twisted pair cables.A twisted pair cable is made up of 2 insulated copper wires twisted around each other in a spiral pattern.
The twisting prevents electromagnetic fields from developing around the two wires as they transmit data.
Twisted pair cables can be used to transmit both voice & data signals (i.e., analogue & digital signals). Types of twisted pair cables.The 2 common types of twisted pair cables are:
Unshielded twisted pair (UTP) cables.UTP cables do not have a shield that prevents electromagnetic interference (also called ‘Electric noise’) from the environment.
UTP cable is prone to noise & signal interference, and therefore, not suitable for environments that are electrically ‘noisy’.
Noise may come from lightening sparks, radio signal, or radiations from spark plugs in motor vehicles. Shielded twisted pair (STP) cables.In STP cables, a braided shield is wrapped around the wires to protect them from noise.
Twisted pair cables are grouped into 5 categories according to the type of data transmitted, and the maximum rate of transmission.
Advantages of Twisted pair cables.
Disadvantages of Twisted pair cables.
Coaxial cables.A Coaxial cable resembles the cable that is used to connect television antenna to a television set.The cable has;
The braid together with the insulator & the foil shield protects the carrier wire from Radio Frequency Interference (RFI) and Electromagnetic Interference (EMI). Coaxial cables have bandwidths of up to 1 Gbps (Gigabits per second). Hence, they can be used to link/connect different networks between buildings, and route trunk calls in telecommunication companies. The Two types of coaxial cables.(i). Thin coaxial cable (Thinnet): - it has 1 dielectric insulator around the core.(ii). Thick coaxial cable (Thicknet): - it has 2 dielectric insulators around the core, and is thicker than the thinnet.
Advantages of coaxial cables.
Disadvantages of coaxial cables.
Review questions.
TYPES OF COMPUTER NETWORKSComputer networks are usually classified according to size. The three most common types of networks are:
Local Area Network (LAN).
This is a computer network that is formed whenever computers are connected together in a relatively small geographical area, e.g., in one building or a school. LAN is the smallest size of network & it normally covers an area within the radius of 10M – 3 Km. LAN is usually owned by one organization. However, one LAN can be connected to other LANs over any distance via data transmission lines or wireless media. A LAN connects several Personal Computers to a Server computer. The server computer makes available the resources requested by the other computers (workstations) on a network.
In most LANs, each workstation has its own CPU which it uses to execute programs, but still the workstation user can also access data & devices anywhere on the network. Advantages of LANs.
Metropolitan Area Network (MAN).A MAN is made up of many LANs connected together.It covers a metropolitan (medium-sized geographical) area, e.g., a town or an entire city, within a radius of 5 – 50 Km. Characteristics of MAN
Wide Area Network (WAN).This is the largest size of network.A WAN covers a large geographical area such as an entire country, a continent, or even the whole world. It consists of many LANs and MANs connected together to form one large network such as the Internet.
Characteristics of WAN
Differences between a Local Area Network and a Wide Area Network.
Review questions.
LIMITATIONS (DISADVANTAGES) OF NETWORKING1). Security issuesData & information held on a network is open to many people across the world, and can easily be accessed illegally. In addition, when information is sent over the network from one place to another, it can be tapped or listened to by unauthorized parties.2). High initial costThe initial cost of buying network hardware & software is very high.3). Moral and cultural effectsLarge networks such as the Internet have chat rooms and messaging services. These enable underage children to meet peers and adults on the net, some of whom may have bad intentions.
Access to pornographic and other negative material on the Internet has made the fight against social problems such as HIV/AIDS, bad sexual behaviour, and drug abuse more complicated. 4). Spread of terrorism and drug traffickingThe Internet makes it easy for terrorists and drug traffickers to operate. This is because; they use information networks for their business communications.5). Over-reliance on networks.Most organizations have done away with manual operations. This means that, all business processes, and the society depend on computer networks. Therefore, if by any chance the network fails or goes down, then many systems in the society will stop working. |
AuthorAtika School Team Archives
November 2021
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