JSS 2 First Term

Learning Objectives

• Define a computer and state its main characteristics.
• Name the early computing devices in order.
• Describe the five generations of computers.
• Classify computers by size, purpose and technology.

What is a Computer

A computer is an electronic device that accepts data, processes it according to a set of instructions called a program, and produces useful output called information. The word computer comes from compute, which means to calculate.

Modern computers do far more than calculate. They store photographs, play music, send messages and control machines. Their main characteristics are speed, accuracy, storage ability, automation and versatility.

A computer is more flexible than a calculator. A calculator does only arithmetic, while a computer can be programmed to do many different jobs.

Early Computing Devices

The abacus is one of the oldest counting devices. Beads slide on rods to stand for numbers, and it was used in China, Greece and Rome long before calculators existed.

In 1617 John Napier invented Napier's Bones, a set of numbered rods that made multiplication and division faster.

In 1642 Blaise Pascal built the Pascaline, a machine with gears that could add and subtract.

In 1801 Joseph Jacquard built a loom controlled by punched cards. The idea that a card could carry instructions was later used in computers.

In the 1820s Charles Babbage designed the Difference Engine to calculate mathematical tables. He then designed the Analytical Engine, which had a store for data and a mill for processing, and it is regarded as the first design for a programmable computer. Ada Lovelace wrote instructions for it and is called the first computer programmer.

The First Electronic Computers

The first electronic computers appeared in the 1940s. ENIAC, the Electronic Numerical Integrator and Computer, was built in the United States and used about seventeen thousand vacuum tubes. It weighed about twenty seven tonnes and filled a room, yet could perform about five thousand additions each second.

UNIVAC, the Universal Automatic Computer, was delivered in 1951 and was the first electronic computer sold commercially.

Generations of Computers

A generation is a major stage in the development of computers, marked by a change in the main technology.

The first generation used vacuum tubes, with ENIAC and UNIVAC I as examples. The second generation used transistors, which were smaller and more reliable, with the IBM 1401 as an example. The third generation used integrated circuits, with the IBM System/360 as an example. The fourth generation used microprocessors, which made the personal computer possible. The fifth generation uses artificial intelligence.

Each generation made computers smaller, faster, cheaper and more reliable than the one before.

Classification of Computers

Classification means grouping things together because they share similar features. Computers are classified by size, by purpose and by technology.

By size, a supercomputer is the fastest and largest, used for weather forecasting and scientific research. A mainframe handles many users at once, such as a bank processing transactions. A minicomputer serves a small group, such as a department in a university. A microcomputer is for one user and includes desktops, laptops and tablets.

By purpose, a general purpose computer can do many different jobs, while a special purpose computer is built to do one job only, such as an automated teller machine or a traffic light controller.

By technology, an analogue computer works with continuous quantities, such as the needle of a speedometer. A digital computer works with the digits 0 and 1. A hybrid computer combines both, as a hospital monitor does when it measures a heart rate and shows a digital reading.

Practical Work

1. Draw a timeline showing the abacus, the Pascaline, the Analytical Engine, ENIAC and a modern laptop.
2. Make a table classifying five computers by size, purpose and technology.
3. Write two differences between an analogue device and a digital device.
4. State the main technology used in each of the five generations of computers.

Scenario-Based Questions

1. A government office in 1970 buys a computer the size of a room that can only do basic calculations. Explain, using the generations, why the older computer was so large and limited.
2. A science museum displays a replica of the CDC 6600 built in 1964. A visitor asks who invented the supercomputer. Using Seymour Cray and Phillip Emeagwali, how would you answer?
3. A school needs a computer for one teacher to type lesson plans and mark exams. Which classification by size and by purpose fits best, and why?
4. A hospital uses a device that measures a patient's heart rate continuously and displays a digital reading. Is it analogue, digital or hybrid? Explain.
5. A car speedometer shows speed by moving a needle along a scale. Why is it classified as an analogue device rather than a digital one?
6. A student types assignments and browses the internet at home. Classify the computer by size, purpose and technology, giving a reason for each answer.
7. A factory uses a machine that adjusts speed from sensor readings but also has a manual dial. What type of technology does it use?

Learning Objectives

• State the three parts of a computer system.
• Classify hardware into input, processing, output and storage.
• Distinguish between system software and application software.
• Explain how hardware, software and peopleware work together.

What is a Computer System

A computer is more than a box of wires and chips. To be useful it needs three parts working together: hardware, which is the physical body you can touch; software, which is the set of instructions that tells the hardware what to do; and peopleware, which is the people who use and maintain the system.

If you remove the hardware, the software has nothing to run on. If you remove the software, the hardware has no instructions. If you remove the peopleware, no one gives purpose to the system.

Hardware: The Physical Parts

Hardware is every physical part of the computer that you can see and touch. It is grouped by the job it does.

Input hardware sends data in, such as the keyboard, mouse, scanner, microphone and webcam. Processing hardware does the work, such as the CPU, which is the brain of the computer, and RAM, which holds data temporarily while the computer works. The motherboard is the main circuit board that connects all the parts.

Output hardware presents results, such as the monitor, printer, speakers and projector. Storage hardware keeps data permanently, such as the hard disk, solid state drive, flash drive, memory card and optical disc.

Software: The Instructions

Software is the collection of programs and instructions that tell the hardware what to do. It is intangible, which means you cannot touch it, but it is essential. Software falls into two broad families.

System software manages the computer itself. The most important example is the operating system, such as Windows, macOS, Linux, Android and iOS. Other examples are device drivers, which help the operating system talk to hardware, and utilities such as antivirus and file compression tools.

Application software helps a user do a task, such as a word processor, a spreadsheet, a presentation program, a web browser, a database and graphics software.

Utility means a program that maintains the computer, such as antivirus software.

Peopleware: The Human Element

Peopleware refers to the people who use, operate, maintain and design computer systems. A computer is a tool, and tools are useful only when a person uses them properly.

The end user interacts directly with the computer, such as a student or a bank cashier. The programmer writes the software. The system administrator maintains the network and keeps the computers running. The technician repairs hardware when it breaks. In a school computer lab, both the teacher and the learners are part of the peopleware.

How the Three Parts Work Together

When you press a key on the keyboard, which is hardware, the operating system, which is system software, receives the signal and sends it to the word processor, which is application software, and the letter appears on the screen, which is more hardware. The learner, who is peopleware, reads it and decides what to type next.

This cycle repeats thousands of times a minute, and it works only when all three parts are present and working together.

Practical Work

1. List three examples each of input, processing, output and storage hardware on the school computers.
2. Open the computer and point to the CPU, RAM and motherboard with your teacher.
3. Write five application programs on the computer and state the task each one does.
4. Make a table with the headings Hardware, Software, Peopleware and place ten items correctly.

Scenario-Based Questions

1. A school buys ten new computers but installs no software. Can the computers be used for teaching? Explain why or why not.
2. A programmer writes a good game but the school computers are too old to run it. Which part of the computer system is failing, and what could the school do?
3. A lab has a skilled technician, fast hardware and the latest software, but no learners come. Is the computer system useful? Why or why not?
4. A student is typing an essay when the screen goes blank, but the computer is still running. Which type of failure is most likely: hardware, software or peopleware? Explain.
5. A shop owner wants to record sales, print receipts and check stock. Which part of the computer system does each task rely on?
6. A school plans to remove the computer technician because the new computers have a two year warranty. Explain why this could cause problems.
7. Explain the difference between system software and application software using two examples of each.

Learning Objectives

• Define an operating system and state its functions.
• Compare a graphical user interface and a command-line interface.
• Explain files, folders and drives.
• Practise good file management skills.

What is an Operating System

An operating system is the most important piece of system software on a computer. It is the first program to load when the computer is switched on, and it manages all the hardware and software resources of the computer.

Common operating systems are Windows, used on most desktop and laptop computers; macOS, used on Apple computers; Linux, which is free and open source; Android, used on many phones and tablets; and iOS, used on iPhones and iPads.

Functions of an Operating System

The operating system manages hardware by communicating with the keyboard, mouse, monitor, printer and other devices. It manages memory by deciding which programs use the RAM and how much each one gets. It manages files and folders by keeping track of where everything is stored.

It provides a user interface so that a person can control the computer. It manages programs by loading them, running them and closing them, and it reports errors when something goes wrong.

Graphical and Command-Line Interfaces

A graphical user interface, or GUI, lets the user interact using pictures called icons, windows and menus with the mouse. Most people use a GUI because it is easy to learn.

A command-line interface, or CLI, requires the user to type text commands. On Windows it is opened through the Command Prompt, and on Linux and macOS it is called the Terminal. A CLI is faster for experts but harder for beginners.

Files, Folders and Drives

A file is a named collection of data stored on a computer. Every file has a name and an extension that shows its type. For example, essay.docx is a document and photo.jpg is a picture. The extension tells the operating system which program to use to open the file.

A folder, also called a directory, is a container used to organise files. Folders can hold other folders, called sub-folders, giving a tree of folders. A drive is a storage area such as the C drive. A USB flash drive may be labelled D or E.

File extension means the part of a file name after the dot that shows its type.

File Management Skills

Good file management makes work easy to find. Use clear, descriptive names instead of names like Document1. For example, save a file as JSS2 Science Essay Week3. Save each file in the correct folder, and save your work often using Ctrl and S.

To create a folder, right-click on an empty area, choose New and then Folder. To rename, right-click and choose Rename. To move a file, drag it to the new folder. To copy it, hold Ctrl while dragging. Deleted files go to the Recycle Bin and can be restored until the bin is emptied.

Practical Work

1. Create a folder called School Work on the desktop, then create three sub-folders inside it.
2. Rename one file correctly, move a file into a folder and copy a file to a flash drive.
3. Delete a file, then restore it from the Recycle Bin.
4. Open the Command Prompt and type dir to list the files in a folder.

Scenario-Based Questions

1. Emeka saves his project as Document1 on the desktop. Two weeks later he cannot remember what it contains. What naming mistake did he make, and how should he have saved the file?
2. Kemi wants to keep her schoolwork organised. Describe the steps to create a folder called Science Project on the main hard drive.
3. Amina finishes a poster and wants a copy on her flash drive while the original stays on the desktop. Should she copy or move the file? Explain.
4. Tunde deletes a report by mistake. Where can he look before the file is permanently lost, and how does the Recycle Bin work?
5. Chidi is typing a long essay when the power goes off and he had not saved. Explain why saving often matters and give the keyboard shortcut he could have used.
6. Fatima downloads a file called report.pdf and it opens in the wrong program. Using file extensions, explain why this happened and how to fix it.
7. Explain two differences between a graphical user interface and a command-line interface.

Learning Objectives

• Define a computer network and its purpose.
• Name the types of networks by coverage.
• State the advantages and limitations of networks.
• Compare client-server and peer-to-peer networks.

What is a Computer Network

A computer network is a group of two or more computers connected so that they can share data, programs and resources. Networks make communication faster, reduce the copying of files and allow many people to use the same information at once.

Common reasons for using a network include sharing files and data, sharing hardware such as a printer or scanner, communicating through email and messaging, saving money by sharing one device, and managing all the computers from one place.

Types of Networks

A local area network, or LAN, covers a small area such as one building or campus. It is the most common network in schools and offices, and it is fast because the devices are close together.

A metropolitan area network, or MAN, covers a larger area such as a city. A university with several buildings connected across a city is a MAN.

A wide area network, or WAN, covers a very large area such as a country or the whole world. The internet is the largest WAN. A bank with branches in several cities uses a WAN. A personal area network, or PAN, connects devices around one person, such as a phone and a wireless earpiece.

Advantages of Networks

Networks allow many users to share one printer, one internet connection or one server. Users can open the same files from different computers, and messages can be sent between users at once.

Networks save money because fewer devices are bought, they keep files safely on one server, and they let people work together on the same project from different computers.

Limitations of Networks

Networks have disadvantages. Setting one up can be costly because cables, switches, routers and a server are needed. Connected computers are open to viruses and attackers, and a virus on one computer can spread to all.

Networks also need regular maintenance and skilled staff. If the server fails, many services stop, and if there is no proper backup, data can be lost. Managing a network also requires technical knowledge.

Client-Server and Peer-to-Peer Networks

In a client-server network, one powerful computer called the server provides services and data to the other computers, called clients. The server controls access and stores files centrally. Most schools and businesses use this type because it is easier to manage and more secure.

In a peer-to-peer network, every computer is equal and can act as both a client and a server. There is no central controller. This type is simpler and cheaper but harder to manage and less secure, and it suits small home networks.

Practical Work

1. Draw and label a simple LAN of five computers sharing one printer and one internet connection.
2. List two advantages and two limitations of a computer network from the school lab.
3. Classify these networks as PAN, LAN, MAN or WAN: a home network, a school lab, a city network and the internet.
4. Write two differences between a client-server network and a peer-to-peer network.

Scenario-Based Questions

1. A small school with five computers asks whether it needs a network. Give two reasons why a network is still useful even with so few computers.
2. A company has offices in Abuja, Lagos and Port Harcourt. What type of network connects the offices, and why is it not a LAN?
3. A virus spreads to all the computers in a bank overnight. Which limitation of computer networks does this show?
4. A community library sets up five computers that share one printer and one internet connection. Is this client-server or peer-to-peer? Explain.
5. A small business owner is told that setting up a network will cost a lot. List two advantages that could convince him.
6. A hospital network goes down and no doctor can reach the patient records. Explain one disadvantage of relying on a network and suggest a way to reduce the risk.
7. Explain why the internet is described as the largest WAN in the world.

Learning Objectives

• Name the hardware components of a network.
• Describe the common network topologies.
• Explain the parts of internet infrastructure.
• State rules for safe use of the internet.

Network Hardware Components

A network interface card, or NIC, is a part inside or attached to a computer that lets it join a network. It changes data from the computer into a form that can travel along cables, and changes incoming data back again.

A hub connects several computers but sends data to every computer connected to it, so it wastes traffic. A switch is smarter: it checks the destination and sends data only to the intended computer, so it is faster and is used in modern networks.

A router connects different networks, such as a school network and the internet. A modem converts digital data into signals that travel over telephone or cable lines, and back again. Network cables, such as Ethernet and fibre optic cables, carry the data, while a wireless access point sends data through radio waves for Wi-Fi.

Network Topologies

A topology is the layout of the computers and cables in a network. The choice of topology affects speed, reliability and cost.

In a bus topology all computers share one backbone cable. It is cheap but one break stops the whole network. In a star topology every computer connects to a central switch, so one broken cable affects only that computer, and it is the most common layout in modern schools and offices.

In a ring topology computers form a closed loop and data travels in one direction, but one break can stop the network. In a mesh topology every computer connects to every other, giving the greatest reliability but at a high cost. A hybrid topology mixes two layouts.

Internet Infrastructure

The internet is a global network of networks. It relies on several parts working together.

Servers are powerful computers that store websites, applications and data. Internet service providers, or ISPs, are companies that give users access to the internet, such as MTN, Glo, Airtel and Spectranet in Nigeria. Submarine cables are long fibre optic cables laid across the ocean floor that carry most traffic between continents. A data centre is a secure building that houses many servers.

Online Safety and Safe Surfing

Using the internet safely is an important skill. Strong passwords are the first line of defence against unauthorised access, and they should be long and private.

Learners should visit trusted websites, check that the address begins with https before entering personal details, and avoid clicking strange links or pop-ups. Personal information such as a full name, address and phone number should not be shared publicly. Suspicious messages should be reported to a trusted adult.

Digital Communication Tools

The internet provides many ways to communicate. Email sends messages and files across the world. Messaging apps send short messages, photos and documents. Voice and video calls let people speak and see each other over the internet. Social media lets users share posts, photos and videos with a wide audience.

Every online user should follow netiquette, which is the set of polite rules for communicating online. Good netiquette includes using a respectful tone and not sharing other people's private information.

Practical Work

1. Draw and label star, bus, ring and mesh topologies.
2. Locate the switch, router and cables in the school computer lab and state the job of each.
3. Write three safe surfing rules on a chart for the computer lab.
4. List three digital communication tools and state what each one is used for.

Scenario-Based Questions

1. A school lab has ten computers connected to one switch. What topology is this, and why is a switch better than a hub here?
2. A bank needs a network that keeps working even if one connection fails. Which topology is most suitable and why?
3. A school has a tight budget but needs a reliable network for thirty computers. Which topology would you recommend and why?
4. A company office connects each computer to a central device. If the central device fails, all lose connection. What topology and central device is this, and what is its main weakness?
5. A government agency needs the highest reliability. A technician suggests mesh. Explain why mesh is the best choice and give one disadvantage.
6. A small office has six computers and an employee suggests a bus topology to save cable cost. Give one advantage and one disadvantage of the suggestion.
7. Explain two rules for safe surfing that a learner should follow.

Learning Objectives

• Describe the internet and the World Wide Web and how they differ.
• Explain the work of browsers, search engines and email.
• State common internet terms and online services.
• Apply safe internet habits and good netiquette.

What is the Internet

The internet is the largest computer network in the world. It connects millions of smaller networks across every country. It began in the late 1960s as a project of the United States Department of Defence, which built a network called ARPANET in 1969 to connect four university computers.

ARPANET used packet switching, which breaks data into small blocks called packets that travel independently and are put back together at the destination. In 1983 the network adopted a set of rules called TCP/IP, which let different networks communicate, and the joined networks became known as the internet.

The World Wide Web

The World Wide Web, often called the Web, is a system of linked web pages and websites accessed through the internet using a browser. The Web is a service that runs on the internet, but it is not the same as the internet. Think of the internet as the roads and the Web as the buildings along them.

In 1989 Tim Berners-Lee proposed the Web. He created HTML for writing web pages, URLs for addressing them and HTTP for transferring them. A web browser, such as Chrome, Firefox, Edge or Safari, finds a web page using the domain name system and displays it on the screen.

Search Engines

A search engine is a tool that helps you find information on the internet. You type keywords and it shows a list of matching pages. Google is the most widely used, and others include Bing, Yahoo, DuckDuckGo and Baidu.

Search engines use programs called crawlers that scan web pages and record their content in a huge index. When you search, the engine matches your keywords against the index and returns the most relevant results.

Email

Email, short for electronic mail, is one of the oldest internet services. It lets a user send and receive messages and files digitally. An email address has three parts: the username, the at symbol and the domain name, as in fatima@creativebrains.edu.ng.

When writing an email, the To field holds the address, the Subject gives a short description, the Body holds the message, and Attachments are files such as documents or images added to the message.

Online Services and Internet Terms

The internet provides many services. Online banking lets people manage accounts and pay bills. Online shopping lets people buy and sell, with Jumia and Konga in Nigeria. Online education provides courses and lessons. Other services include health, social media, cloud storage and entertainment.

Several terms are used every day. Upload means sending a file to a server, and download means bringing a file to your device. A client requests services and a server provides them. A website is a collection of linked pages, and a web page is one document on a website. FTP moves files, VoIP carries voice calls over the internet, and streaming plays audio or video without a full download.

Safe Internet Habits and Netiquette

Safe habits protect a learner online. Never share personal information on public sites, use strong passwords, think before clicking links and check that a site uses https before entering details. Treat information with care and report anything suspicious to a trusted adult.

Netiquette is the set of polite habits for communicating online. Use a kind tone, avoid writing in capital letters, think before sharing a photo of another person, and never spread rumours or false news.

Practical Work

1. Open a browser and visit a trusted website, then save the page to your favourites.
2. Use a search engine to find information on a topic and write down the steps you followed.
3. Send an email with a subject line and one attachment.
4. Write five safe internet habits on a chart and display it in the computer lab.

Scenario-Based Questions

1. Fatima sends an email and also visits a website. Does she use the internet for both activities? Explain how the internet and the Web are related but different.
2. A student searches for the history of Nigeria on Google and clicks the first result. Trace the steps from typing the search to seeing the page, naming the technologies involved.
3. A classmate shares a bank PIN on a messaging app. What risk does this create, and what would you advise?
4. You receive an email saying you have won one million naira and asking for your bank details. Using phishing, explain why it is suspicious and what you should do.
5. A parent asks a child to check whether a website is safe before entering personal information. What two things should the child check?
6. Explain three online services the internet provides, with one example of each.
7. Explain why the internet is not the same as the World Wide Web.

Learning Objectives

• Define cloud computing and cloud storage.
• Name common cloud storage services.
• Explain how files synchronise.
• Compare cloud storage with offline storage.

What is Cloud Computing

Cloud computing means using the internet to store data and use programs instead of keeping everything on your own computer. The cloud is not a cloud in the sky. It is a network of powerful computers called servers, kept in data centres around the world.

When you save a file in the cloud, it is sent over the internet to a server, and you can open it later from any device that has a connection. Checking email, watching a video and storing photos online are everyday uses of the cloud.

Cloud Storage Services

Google Drive is made by Google and gives about fifteen gigabytes of free storage. OneDrive is made by Microsoft and gives about five gigabytes, and it works well with Windows and Office. iCloud is made by Apple and works with iPhone, iPad and Mac. Dropbox gives about two gigabytes and works on any device.

These services store the same file for you on their servers and let you download or share it from any device.

How Files Synchronise

Synchronisation, or syncing, means keeping files updated across several devices automatically. When you change a file on one device, the cloud service sends the new version to its server, and the same change appears on your other devices.

For example, if Amina writes a note on her phone, the note is already on her laptop when she opens it, without sending the file by email or copying it to a flash drive. Syncing works in the background as long as the devices are online and signed in to the same account.

Benefits and Risks of Cloud Storage

Cloud storage has many benefits. Files can be opened from any device, they are backed up automatically so they survive a broken device, they can be shared with a link, they free up space on your device, and several people can work on the same document at once.

It also has risks. It needs an internet connection, so files cannot be reached offline. Free storage is limited, and accounts can be stolen if passwords are weak. Files are kept on someone else's servers, so users must trust the provider, use strong passwords and turn on two factor authentication.

Offline Storage versus Cloud Storage

Offline storage, such as a USB flash drive, external hard disk, CD or DVD, does not need the internet. It is fast to reach and gives direct physical access, but it can be lost, damaged or stolen.

Cloud storage needs the internet but gives automatic backup and access from anywhere. The best approach is to use both: keep everyday files in the cloud and keep a backup of important files on a flash drive or hard disk.

Cloud Service Models

Cloud services are delivered in three main ways. Infrastructure as a Service, or IaaS, rents out basic resources such as servers and storage. Platform as a Service, or PaaS, gives developers a ready made place to build and run programs. Software as a Service, or SaaS, delivers ready to use programs over the internet, such as Google Drive, OneDrive and Google Classroom.

Practical Work

1. Open a cloud storage service and upload one document, then open it again from another device if available.
2. List three cloud storage services and state the free storage each one gives.
3. Make a table comparing cloud storage and offline storage with three features.
4. Explain in two sentences how file synchronisation works.

Scenario-Based Questions

1. Amina keeps her project only on her laptop. The laptop breaks and she loses all her work. What backup method could she have used, and how would cloud storage have helped?
2. Tunde uploads a photo to Google Drive at school and sees the same photo on his phone at home. Explain how synchronisation makes this possible.
3. A rural school has very slow internet and needs to give students large video files. Should the teacher use cloud storage or flash drives? Give a reason.
4. Explain the difference between uploading and downloading a file, with one example of each.
5. A company keeps all its files only in the cloud. A manager argues for offline backups as well. Explain why the manager is right.
6. A student says cloud storage is free so a flash drive is not needed. Give one advantage and one risk of relying only on cloud storage.
7. Explain why a cloud storage account should be protected with a strong password.

Learning Objectives

• Define cybersecurity and explain why it matters.
• Identify common online threats and types of malware.
• Describe phishing and how to avoid it.
• Apply strong passwords, two factor authentication and safe browsing.

What is Cybersecurity

Cybersecurity is the practice of protecting computers, networks, programs and data from unauthorised access, damage or attack. Almost everything we do online involves personal data, so every internet user needs basic cybersecurity knowledge.

Just as you lock the door of your house, you must protect your digital life with strong passwords, careful habits and awareness of online threats.

Common Online Threats and Malware

Malware is short for malicious software. It is any program written to harm a computer or steal data. A virus attaches itself to a program and spreads when that program runs. A worm spreads across a network on its own. A Trojan horse pretends to be a useful program so that a user installs it. Ransomware locks files and demands payment to unlock them. Spyware watches what you do and steals information.

Malware can enter a computer through suspicious downloads, infected flash drives, harmful links or unsafe websites. Antivirus software and regular system updates are important defences.

Phishing

Phishing is a scam in which a person pretends to be a trusted organisation, such as a bank or school, to trick you into giving away personal information. Phishing messages often create a sense of urgency, such as saying an account will be closed or that you have won a prize.

Signs of phishing include threatening or urgent language, a strange sender address, a greeting such as Dear customer instead of your name, links to unknown websites and requests for passwords or bank details. Do not click any links, do not reply, check the source and report the message to a trusted adult.

Identity theft means using stolen personal details to pretend to be someone else.

Strong Passwords and Two Factor Authentication

A strong password is long and mixes capital letters, small letters, numbers and symbols. It should not be a common word, a name or a date of birth. Do not reuse the same password on different sites, because if one account is stolen the others stay safe with different passwords. A passphrase, such as I#Love_Science2026, is strong and easy to remember.

Two factor authentication, or 2FA, requires a second proof of identity after the password, such as a code sent to the phone. Even if a password is stolen, the account stays safe without the second code.

Safe Browsing and Protecting Personal Information

Safe browsing means checking that a website uses https and shows a padlock before entering any personal information, keeping the browser updated and not downloading files from unknown sources.

Personal information includes your full name, address, phone number, school and bank details. It is valuable to criminals, so use a nickname online, keep profiles private and never share passwords or bank details on untrusted websites.

Social Media Safety and What To Do

Social media has privacy settings that control who sees your posts, profile and location. Review these settings and keep them strict, never accept requests from strangers and do not post your location in real time.

When something online feels wrong, trust your instincts. Do not click, do not share and tell a trusted adult. Report suspicious messages, block strangers, and if a link was clicked by mistake, run an antivirus scan and change your passwords.

Practical Work

1. Create a strong password for a sample account and explain why it is strong.
2. Turn on two factor authentication on a school or personal account if allowed.
3. List five signs that an email may be a phishing attempt.
4. Write five protection measures on a chart for the computer lab.

Scenario-Based Questions

1. Chidi receives an email from his bank asking him to click a link and enter his account number. The email was sent to his personal address, not his bank address. Using phishing, explain why it is suspicious and what he should do.
2. The school computers suddenly run very slowly and pop-ups appear. The teacher says malware is responsible. Explain which type could be responsible and how it entered the system.
3. Amina uses the same password, 123456, for her school portal, email and social media, while Tunde uses a different strong password for each. Compare their approaches and explain why Tunde is safer.
4. Bola notices the address bar shows a padlock and starts with https. Explain what these mean and why they matter.
5. Kemi downloads a free game from an unknown site and her photos later appear online. Identify the malware and explain how it got onto her computer.
6. A school plans a cybersecurity programme. List three rules it should teach students.
7. Emeka is asked for his home address and phone number before viewing an article. Explain what he should do and why sharing on unknown sites is risky.

Learning Objectives

• Distinguish between data and information.
• Name common sources of data.
• Explain how data becomes information.
• Describe personal data and how to protect it.

Data and Information

Data is raw, unprocessed facts and figures. It can be numbers, words, images or sounds, and on its own it does not tell you anything useful. The numbers 85, 72, 90, 68 and 77 are just numbers until you know what they represent.

Information is data that has been processed, organised and presented in a way that gives it meaning. When a teacher writes Student Names and Science Test Scores above those numbers, they become information. The same data can give different information depending on how it is processed.

Sources of Data

Data comes from many sources. Forms and questionnaires collect data when people fill in registration or hospital forms. Surveys and interviews collect data by asking questions. Sensors and instruments collect data automatically, such as weather stations recording temperature.

Other sources are online transactions, school records, social media activity and government records such as a population census. Every time you fill a form, take a test or browse a website, you generate data.

Structured data means data arranged in a clear format such as a table.

Unstructured data means data with no fixed format, such as photos or voice notes.

How Information is Produced

Data becomes information in four steps. First, raw data is collected from a source. Second, it is organised in a logical order, such as sorting scores from highest to lowest. Third, it is processed by calculating, sorting or grouping. Fourth, the result is presented in a useful form, such as a chart or a report.

A hospital collects patient temperatures, organises them by time, processes them to spot fever cases and presents the information to doctors for decisions.

Primary source means a source where data is collected first hand.

Secondary source means a source that provides data collected by someone else.

Personal Data

Personal data is any information that can be used to identify a person. It includes your full name, date of birth, address and phone number; financial data such as bank details; educational data such as results; health data such as medical records; and online data such as passwords and browsing history.

Personal data is valuable and must be kept safe, because criminals can use it to steal money or pretend to be you.

Data Protection

Data protection is the practice of keeping personal data safe from unauthorised access, loss or misuse. Organisations should collect only the data they need, keep it secure, use it only for the stated purpose, delete it when it is no longer needed, allow people to see their own data and obtain consent before collecting it.

In Nigeria the Nigerian Data Protection Regulation, or NDPR, requires organisations to protect the personal data they collect. Schools, banks and hospitals must follow these rules.

Protecting Personal Data and Responsible Handling

To protect personal data, use strong passwords, turn on two factor authentication, keep software updated, avoid sharing personal details publicly and back up important files. On shared computers, sign out when you finish.

Responsible handling means treating other people's data with care. Do not post a classmate's results without permission, use survey data only for the school project, delete old files holding personal information and report any misuse of data.

Practical Work

1. Collect the marks of ten pupils and turn the raw data into information by finding the average and the highest score.
2. List five sources of data and give one example of each from your school.
3. Write three rules of data protection and explain each in one sentence.
4. State three ways to protect your personal data online.

Scenario-Based Questions

1. A school collects students' names, dates of birth and home addresses on a registration form. Classify this as data or information and explain the difference.
2. A hospital records a patient's temperature, blood pressure and weight. A doctor then writes a diagnosis. Explain how the raw measurements become useful information.
3. A social media app asks for a new user's location, contacts and photo gallery. Explain why this raises concerns about personal data.
4. A classmate posts another student's exam results in the class group without permission. Explain why this is wrong, using data protection ideas.
5. A company keeps customer records only on one laptop. The laptop is stolen and the records are lost. Explain why both a cloud backup and an offline backup are important.
6. Give two ways a school could follow the NDPR when collecting student information.
7. Give two ways to protect your personal data online.

Learning Objectives

• Describe a spreadsheet and its main parts.
• Enter data, formulas and functions in a spreadsheet.
• Describe a presentation and the parts of the presentation window.
• Create and present a short slide show.

Introduction to Spreadsheets

A spreadsheet is a program used to arrange numbers and text in rows and columns and to perform calculations quickly. It is used for accounts, marks, budgets and record keeping. Microsoft Excel and Google Sheets are common examples.

A spreadsheet file is called a workbook, and it contains one or more sheets called worksheets. The point where a row and a column meet is a cell, and each cell has an address such as A1 or B5. A row runs across the sheet and is named by a number, while a column runs down the sheet and is named by a letter.

Working with a Spreadsheet

Data is typed into cells, and the active cell is the one selected. To calculate, a formula begins with the equals sign, such as =A1+A2. A function is a ready made formula, such as =SUM(A1:A10) to add a range of numbers or =AVERAGE(A1:A10) to find the mean.

A chart turns numbers into a picture, such as a bar chart or a pie chart, which makes the data easier to understand. Charts are inserted from the Insert menu, and the chart type is chosen to suit the data.

Introduction to Presentations

A presentation is a slide show used to present information to an audience. Microsoft PowerPoint and Google Slides are common examples. A presentation is made of slides, and the first slide usually holds the title and the presenter's name.

The presentation window has a slide pane that shows the slides in order, a editing area for the current slide, a ribbon of tools and a status bar. A slide master controls the layout and style of every slide, and a template gives a ready made design.

Creating and Presenting Slides

To create slides, add a title and bullet points, then insert pictures, shapes or charts where they help. Keep text short, use a clear font and use one idea per slide. New slides can be added and moved, and content can be resized or deleted.

To present, use Slide Show mode, move forward with the arrow keys and speak clearly to the audience. Save the presentation often, and export it or print it as handouts when needed.

Practical Work

1. Open a spreadsheet and enter the marks of five pupils in a column, then use SUM and AVERAGE to find the total and the mean.
2. Insert a bar chart from the marks and give it a title.
3. Open a presentation program and create three slides: a title slide, a slide with bullet points and a closing slide.
4. Add one picture to a slide and run the slide show.

Scenario-Based Questions

1. A teacher wants to record the marks of forty pupils and find the average. Explain why a spreadsheet is better than a paper exercise book for this task.
2. A pupil types 45 into cell A1 and 55 into A2, then wants the total in A3. Write the formula the pupil should type.
3. A school wants to show how many pupils chose each of four clubs. Which chart type is best, and why?
4. A presenter puts a long paragraph on one slide. Explain two ways to make the slide easier to read.
5. Explain the difference between a workbook and a worksheet.
6. Explain how a chart helps a user understand spreadsheet data.
7. Describe the steps to add a new slide and save a presentation.

Learning Objectives

• Revise all topics of the term.
• Answer objective and short answer questions accurately.
• Identify the topics that need more practice.
• Prepare a plan for the examination week.

Review of the Term

The term began with the classification of computers and the parts of a computer system: hardware, software and peopleware. It then studied the operating system and file management, and moved on to computer networks and the devices that connect them.

The second half looked outward and forward. The internet and the World Wide Web were studied, together with online services and cloud storage. Cybersecurity and online safety showed how to stay safe, and data protection showed how to handle personal data. The term closed with spreadsheets and presentations.

Revision Method

Revise by topic, not by page. Start with the list of topics and check that you can explain each one. Define a network in one sentence. Name the four network topologies. State three functions of an operating system. Explain the difference between the internet and the World Wide Web.

Then check practical skills. Can you create a folder and save a file with a clear name? Can you make a simple spreadsheet formula and a chart? Can you create and present a short slide show?

Common Weak Areas

Learners often confuse a hub with a switch and a router. The test is simple: a hub sends data to everyone, a switch sends data to the intended computer, and a router connects different networks.

Another weak area is data and information. Data is raw and meaningless on its own; information has been processed and given meaning. Learners also confuse the internet with the World Wide Web, and forget that the Web is one service on the internet.

Practical Work

1. Create a folder, save a file with a clear name and restore a file from the Recycle Bin.
2. Make a spreadsheet with a SUM and an AVERAGE function and insert one chart.
3. Create a three slide presentation and present it to the class.
4. List every weak topic found in the test and write one practice activity for each.

Scenario-Based Questions

1. In one sentence, define a computer network and name its four types by coverage.
2. Explain the difference between a hub and a switch.
3. Explain the difference between the internet and the World Wide Web.
4. Give two safe internet habits and explain why each one matters.
5. Explain how cloud storage keeps a file safe if a device breaks.
6. Explain the difference between data and information with one example.
7. State three functions of an operating system.

Examination and Continuous Assessment Practice

These questions are taken from the First Term examination and Continuous Assessment papers for this class. Answer them in full sentences.

1. (a) Define a Computer. (b) Mention and explain the three (3) classifications of computers based on their operating principles (type). (c) List four (4) classifications of computers based on size and capacity.
2. (a) State four (4) important rules and regulations to be observed in the computer laboratory. (b) Explain what is meant by Ergonomics in computer usage. (c) Mention two (2) ways to properly care for and maintain computer hardware equipment.
3. (a) Briefly describe the stages involved in the Data Processing Cycle. (b) Define Information Transmission. (c) Mention two (2) ancient methods and two (2) modern methods of transmitting information.
4. (a) Highlight the main technological components used in each of the first four generations of computers: (i) First Generation (ii) Second Generation (iii) Third Generation (iv) Fourth Generation (b) Mention two (2) early calculating or counting devices invented before modern computers. (c) State two (2) contributions of Charles Babbage to computer history.
5. A classmate says a calculator is a computer. Explain what a computer is, state why it is different from a simple calculator, and give three things a modern computer can do beyond calculation.
6. A school history project wants to explain why the Jacquard loom matters to computing. Describe the early counting tools, explain the contribution of the Pascaline, and state why the Jacquard loom is described as an ancestor of computer programming.
7. A display case in a museum holds an ENIAC and a UNIVAC. State who built ENIAC, when, and describe its size and power. Then explain what UNIVAC changed.
8. A computer shop assistant must advise a customer. State the years and main technology of the first, second and third generations of computers, give one example machine of each, and explain what the third generation added.

Learning Objectives

• Complete the First Term examination.
• Answer every question within the time allowed.
• Demonstrate practical skills in the laboratory task.
• Use the result analysis to plan the Second Term work.

Examination Arrangements

The First Term examination covers Weeks 1 to 10. The written paper tests understanding of facts, definitions and the ability to explain. The practical task tests whether the learner can actually use a computer.

All learners should arrive early with two pens, a pencil, an eraser, a ruler and an identification card. Practical candidates must confirm that the computer, keyboard and mouse are working before the task begins.

What the Paper Will Test

The paper will include objective questions that test single facts, names and classifications. It will also include short answer questions that test definitions, differences and short explanations. Where provided, essay questions will require that require organised paragraphs.

The practical task may test file management, a simple spreadsheet with a formula and a chart, or the creation of a short slide show. Practise these steps before the examination.

After the Examination

Once the papers are marked, the results should be analysed. Count how many learners lost marks on each question. A question that almost every learner missed shows the topic was not well taught and must be repeated.

Record the topics to be retaught in the Second Term and the topics to move on from, and share the analysis with the class so that learners know which areas to work on.

Preparing for the Second Term

The Second Term begins with revision of the topics that were weak. It then moves to new topics that build on what has been learned, including further work on productivity programs and on using computers safely and responsibly.

Practical Work

1. Enter the examination room with all required materials.
2. Read the instructions and the marks for each section before writing.
3. Attempt every question, beginning with the ones you understand best.
4. Complete the practical task exactly as instructed.

Scenario-Based Questions

1. You have twenty minutes left and four questions unanswered. Explain how you should use the time.
2. A learner finishes the practical task but forgets to save the file. Explain the consequence.
3. Explain why a teacher analyses the examination results before planning the next term.
4. State four items you should bring to the examination.
5. Explain how you would answer a question asking for the difference between two items when you can only remember one.
6. Give two reasons why the practical task is an important part of Digital Technology.
7. A question asks for four items and one mark is given for each. Explain what happens if only two are given.
8. ODELAMI

First Term Examination Practice Questions

These questions are taken from the First Term examination and Continuous Assessment papers for this class. Answer them in full sentences.

1. (a) Highlight the main technological components used in each of the first four generations of computers: (i) First Generation (ii) Second Generation (iii) Third Generation (iv) Fourth Generation (b) Mention two (2) early calculating or counting devices invented before modern computers. (c) State two (2) contributions of Charles Babbage to computer history.
2. (a) Define a Computer. (b) Mention and explain the three (3) classifications of computers based on their operating principles (type). (c) List four (4) classifications of computers based on size and capacity.
3. (a) State four (4) important rules and regulations to be observed in the computer laboratory. (b) Explain what is meant by Ergonomics in computer usage. (c) Mention two (2) ways to properly care for and maintain computer hardware equipment.
4. (a) Briefly describe the stages involved in the Data Processing Cycle. (b) Define Information Transmission. (c) Mention two (2) ancient methods and two (2) modern methods of transmitting information.