Input and Output Devices
Input Devices; Output Devices; Devices That Do Both Jobs; Choosing the Right Device; More Input Devices in Detail; Display Devices and Printers
On this page9 sections
- 01Learning Objectives
- 02Input Devices
- 03Output Devices
- 04Devices That Do Both Jobs
- 05Choosing the Right Device
- 06More Input Devices in Detail
- 07Display Devices and Printers
- 08Practical Work
- 09Scenario-Based Questions
Learning Objectives
- Identify input and output devices found in a computer system.
- State the function of each common device.
- Classify devices that act as both input and output.
- Choose the correct device for a given task.
Input Devices
An input device sends data and instructions into the computer. The keyboard is the main text device. The mouse is the main pointing device. The scanner reads a printed page. The microphone captures sound. A touchscreen receives commands by touch. A webcam captures a live picture.
A joystick or game pad is used in games and in training simulators. A barcode reader is used in shops to read product codes. A digital camera captures still pictures. Biometric devices such as a fingerprint reader and a face scanner are used to control entry to a building or a phone.
Output Devices
An output device presents the result. The monitor shows text, pictures and video and is the most used output device. A printer produces a paper copy. A speaker produces sound. A projector enlarges the screen for a class. A plotter draws large diagrams such as building plans.
A hard copy is a printed output that lasts. A soft copy is an output shown on screen and disappears when the screen is cleared.
Devices That Do Both Jobs
Some devices act as input and output at the same time. A touchscreen shows information and receives touch commands. A multifunction printer prints, scans and copies. A headset both plays sound and records it. Learners should classify such a device by the job being done at that moment.
Choosing the Right Device
Choosing a device depends on the task. To enter text, use a keyboard. To select a menu item, use a mouse or a touchscreen. To send a photograph, use a webcam or a scanner. To produce a permanent copy, use a printer. To record a lesson, use a microphone.
More Input Devices in Detail
A scanner converts printed pages into digital files. A flatbed scanner takes a page on glass, a handheld scanner is moved over the page, and an all in one printer can scan, print and copy in one machine.
Pointing devices move the cursor on the screen. The mouse may be optical, laser or wireless, and a laptop uses a touchpad or a trackball. A barcode reader reads the black and white lines on a product and is used in shops, libraries and hospitals. A joystick controls games and machines, and a light pen points directly at the screen.
Display Devices and Printers
A display device shows information on a screen. Older CRT monitors are heavy and thick, while modern flat screens use LCD, LED or OLED technology. Resolution is the number of pixels, the tiny dots that make up the picture, so a higher resolution gives a sharper image.
A printer puts the result on paper as hard copy. An inkjet printer sprays tiny drops of ink and suits colour photos and small jobs. A laser printer uses toner powder and a laser beam and is fast and sharp for offices. A thermal printer uses heat and is used for shop and bank receipts.
| Input device | Function |
|---|---|
| Keyboard | Enters letters, numbers and symbols |
| Mouse | Points, clicks and selects items |
| Scanner | Reads a printed page into the computer |
| Microphone | Captures sound |
| Webcam | Captures a live picture |
| Touchscreen | Receives commands by touch and shows a display |
| Joystick | Controls movement in games |
| Barcode reader | Reads product codes in a shop |
| Biometric reader | Identifies a person using a fingerprint or face |
| Output device | Function |
|---|---|
| Monitor | Displays text, images and video |
| Printer | Produces a paper copy |
| Speaker | Produces sound |
| Projector | Enlarges the screen for a class |
| Plotter | Draws large diagrams and plans |
| Printer | How it works | Best for |
|---|---|---|
| Inkjet | Sprays tiny drops of ink | Colour photos and small jobs |
| Laser | Uses toner and a laser beam | Fast, sharp office printing |
| Thermal | Uses heat on special paper | Receipts at shops and banks |
Practical Work
- Walk round the laboratory and record ten different devices with their category.
- Use a scanner to scan a page and print the scanned copy.
- Record five seconds of sound with a microphone and play it back.
- Classify ten written device names as input, output or both, and explain each choice in one line.
Scenario-Based Questions
- A school buys a device that prints, scans and copies. Explain why this counts as both an input and an output device.
- A student is asked to type a two page essay. Name the best device and explain why a scanner would not suit the task.
- Explain why a barcode reader in a supermarket reduces the time spent at the payment point.
- Name three output devices and give one use for each.
- A learner wants to read a printed textbook page on a computer. Name the input device needed and explain its use.
- Explain the difference between a hard copy and a soft copy with one example of each.
- A touchscreen computer replaced separate keyboards and mice in a bank. Give two advantages and one disadvantage.
LEARNING OBJECTIVES: BY THE END OF THE LESSON PUPILS SHOULD BE ABLE TO:
| Cognitive | i. Identify input and output devices found in a computer system. ii. State the function of each common device. iii. Classify devices that act as both input and output. iv. Choose the correct device for a given task. |
| Affective | i. Appreciate the value of Input and Output Devices in school, at home and in the community. ii. Show willingness to use digital tools carefully, safely and responsibly. |
| Psychomotor | i. Walk round the laboratory and record ten different devices with their category. ii. Use a scanner to scan a page and print the scanned copy. iii. Record five seconds of sound with a microphone and play it back. iv. Classify ten written device names as input, output or both, and explain each choice in one line. |
Rationale: An input device sends data and instructions into the computer. Understanding input Devices, output Devices, devices That Do Both Jobs, choosing the Right Device helps learners use digital technology confidently, safely and responsibly.
Pre-requisite Knowledge: In Week 4, learners studied Functions of Parts, Hardware and Software, including input and Output Functions, processing and Storage Functions, how the Parts Work Together. The knowledge from that week is used again in this lesson.
Learning Material/Teaching Aid: Whiteboard, markers, computer or laptop where available, printed notes and charts on Input and Output Devices, practical task sheets, learners' notebooks and pens.
Reference Materials: Digital Technology for Junior Secondary Schools (JSS 1); NERDC Digital Technology Curriculum; Digital Technology JSS 1 First Term Notes (Week 5); First Term examination and Continuous Assessment question papers.
LESSON DEVELOPMENT
| Stage/Step (Time) | Teacher's Activities | Student's Activities | Learning Points |
|---|---|---|---|
| Introduction 5 MINUTES | Welcomes learners, revises Week 4 (Functions of Parts, Hardware and Software) with two quick oral questions, and asks what they already know about Input and Output Devices. Elicits responses and writes the topic on the board. | Recall the previous lesson and share what they already know about Input and Output Devices. | Connecting prior knowledge to Input and Output Devices. |
| Step 1 6 MINUTES | Covers Input Devices: An input device sends data and instructions into the computer. The keyboard is the main text device. Covers Output Devices: An output device presents the result. The monitor shows text, pictures and video and is the most used output device. | Listen, take notes and answer oral questions on "Input Devices" and related points. | Understanding: Input Devices; Output Devices. |
| Step 2 6 MINUTES | Covers Devices That Do Both Jobs: Some devices act as input and output at the same time. A touchscreen shows information and receives touch commands. Covers Choosing the Right Device: Choosing a device depends on the task. To enter text, use a keyboard. | Copy the key points, give examples from school and everyday life, and ask questions on "Devices That Do Both Jobs" and related points. | Understanding: Devices That Do Both Jobs; Choosing the Right Device. |
| Step 3 6 MINUTES | Covers More Input Devices in Detail: A scanner converts printed pages into digital files. A flatbed scanner takes a page on glass, a handheld scanner is moved over the page, and an all in one printer can scan, print and copy in one machine. | Discuss in pairs, then report one point on "More Input Devices in Detail" to the class. | Understanding: More Input Devices in Detail. |
| Step 4 6 MINUTES | Covers Display Devices and Printers: A display device shows information on a screen. Older CRT monitors are heavy and thick, while modern flat screens use LCD, LED or OLED technology. Resolution is the number of pixels, the tiny dots that make up the picture, so a higher resolution gives a sharper image. | Respond to questions, complete the examples on the board and note down "Display Devices and Printers". | Understanding: Display Devices and Printers. |
| Practical Work 6 MINUTES | Guides learners through the practical work: (i) Walk round the laboratory and record ten different devices with their category. (ii) Use a scanner to scan a page and print the scanned copy. (iii) Record five seconds of sound with a microphone and play it back. Moves round the class to check progress and correct unsafe or careless use. | Carry out the practical tasks individually or in pairs and record what they did in their notebooks. | Applying the lesson through hands-on practice. |
| Evaluation 3 MINUTES | Asks learners to: i. Identify input and output devices found in a computer system. ii. State the function of each common device. iii. Classify devices that act as both input and output. iv. Choose the correct device for a given task. | Respond verbally and in writing to the evaluation questions. | Assessment and consolidation of the lesson content. |
| Conclusion 2 MINUTES | Recaps the main points: input Devices, output Devices, devices That Do Both Jobs, choosing the Right Device, more Input Devices in Detail. Links them to the assignment and previews Week 6: Basic Typing Skills. | Listen, ask questions and copy the assignment. | Reinforcement of key concepts and a preview of the next lesson. |
Assignment: i. A shopkeeper wants to classify the machines in his shop and choose a keyboard for fast typing. Explain how computers are classified by size and by purpose, define the input and output peripherals, and explain what the QWERTY layout is and why it was designed. ii. A school buys a device that prints, scans and copies. Explain why this counts as both an input and an output device.
On this page9 sections
- 01Lesson objectives
- 02Key vocabulary
- 03Common misconceptions
- 04Teacher activities
- 05Student activities
- 06Practical / learning evidence
- 07Resources and preparation
- 08Assessment for learning
- 09Inclusion and homework
Lesson objectives
By the end of the week, learners should be able to:
- Define input and output devices and state the direction in which data flows for each.
- Classify at least fifteen devices as input, output or both, with a reason.
- Distinguish impact from non-impact printers and give one example of each.
- Explain the difference between soft copy and hard copy.
- Match specialised devices to their real-world setting, such as OMR in examinations and a barcode scanner in a shop.
Key vocabulary
- Input device: sends data or instructions into the computer, such as a keyboard or scanner.
- Output device: presents processed information to the user, such as a monitor or printer.
- Soft copy: output shown on a screen or stored as a file.
- Hard copy: output printed on paper.
- Impact printer: strikes the paper through an inked ribbon, such as a dot-matrix printer.
- Non-impact printer: prints without striking the paper, such as an inkjet or laser printer.
- OMR: optical mark reader, which detects shaded marks such as examination answer sheets.
- OCR: optical character reader, which converts a scanned image of text into editable text.
- Biometric input: identifying a person from a fingerprint, face or iris.
Common misconceptions
- "A printer is an input device because I put paper into it." Paper is not data. The printer receives data from the computer and produces output.
- "A touchscreen is only an output device." It is both. It displays information and accepts touch input.
- "All printers print the same way." Impact printers strike the paper, inkjet printers spray ink, and laser printers use toner and heat.
Teacher activities
- Starter: ask learners to name every device they touched to send a message on a phone, and list them on the board.
- Define input and output by direction of data flow, and draw the diagram on the board.
- Demonstrate or show a keyboard, mouse, scanner, microphone, monitor, speaker and printer, naming each as it is used.
- Explain impact and non-impact printing with a dot-matrix sample and a laser or inkjet sample if available.
- Set the classification table in pairs, including the difficult cases: touchscreen, modem and multifunction printer.
- Close with a setting-matching quiz: OMR, barcode scanner, ATM keypad, projector and plotter.
Student activities
- List the devices used in the starter and identify the input ones.
- Copy the direction-of-flow diagram and label the arrows.
- Handle or view each demonstrated device and write its function in one line.
- Compare the two printed samples and state two differences between impact and non-impact output.
- Complete the classification table of fifteen devices as input, output or both, with reasons.
- Match five specialised devices to the setting where they are used.
Practical / learning evidence
A completed classification table with columns Device | Input/Output/Both | Reason | Where it is used, covering at least fifteen devices, including three that are both. Plus a short written comparison of an impact and a non-impact printer using two named criteria.
Resources and preparation
Keyboard, mouse, scanner, microphone, webcam, monitor, speaker and printer where available. A dot-matrix printout and a laser or inkjet printout for comparison. Pictures of an OMR sheet, barcode scanner, ATM keypad and plotter. Offline route: picture cards and the printed table. No device is needed. Supervise the scanner and printer so learners do not scan personal documents.
Assessment for learning
Check the reason column as well as the input and output label. A guess can produce a correct label, so require the reason. Ask learners to explain the touchscreen case aloud. Mark the printer comparison for two valid criteria such as speed, noise, cost per page or print quality.
Inclusion and homework
Provide picture cards with the device name printed underneath, and allow oral completion of the reason column. Extend confident learners with a question on which printer a school should buy for 500 examination papers, with a justification. Homework: find three output devices in your home or school and write what each one produces.