Year 10 · ICT · Autumn 1
Computer systems, devices and storage; document production · Lesson 3 of 5
Input and output devices
Theory2.1 Input devices2.2 Direct data entry devices2.3 Output devices
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
You will learn to
- Describe the use of common input and output devices.
- Give an advantage and a disadvantage of each device.
- Explain what direct data entry is, with examples such as barcode and RFID readers.
- Choose a suitable device for a given scenario and justify the choice.
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Success criteria
You have got it when you can say:
- I can give a scenario, an advantage and a disadvantage for twenty devices.
- I can explain why a supermarket uses barcode readers, not keyboards, at the till.
- I can answer a past-paper 'which device' question with a justified choice.
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Retrieval starter
Questions from before. Write your answers, then show them.
- Last lesson
Exporting means…
A Saving in a format another program can openB DeletingC Printing
A. Saving in a format another program can open
- Earlier this unit
Selecting Year = 8 before merging…
A Prints everything twiceB Sends letters only to Year 8C Changes the letter text
B. Sends letters only to Year 8
- Last lesson
The data source is…
A The list of recipientsB The printerC The letter
A. The list of recipients
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Key words (1 of 4)
- Input device
- Hardware that sends data or instructions into a computer.
- Output device
- Hardware that shows, prints, plays or does the result of processing.
- Direct data entry (DDE)
- Reading data straight from its source with no manual typing.
- Sensor
- An input device that measures a physical quantity such as temperature.
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Key words (2 of 4)
- Actuator
- An output device, such as a motor or valve, that makes something move or happen.
- OMR
- Optical mark recognition: reads shaded marks in set positions on a form.
- OCR
- Optical character recognition: turns a scanned image of text into editable text.
- RFID
- Radio frequency identification: reads a tag using radio waves, without contact.
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Key words (3 of 4)
- Barcode
- A pattern of lines that stands for a number, read by a light beam.
- QR code
- A square pattern of black and white squares that holds more data than a barcode.
- Chip and PIN
- A bank card chip read by a terminal; the user types a PIN to prove identity.
- Impact printer
- A printer that strikes the paper through an inked ribbon, such as dot matrix.
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Key words (4 of 4)
- Plotter
- An output device that draws very large, accurate drawings.
- 3D printer
- A device that builds a solid object layer by layer.
- Trackerball
- A pointing device where you roll a ball; the device stays still.
2.1 Input devices · The explanation · step 1 of 15 · part 1 of 2
What an input device does
An input device lets data or instructions go into a computer.
Some are manual: a person operates them, like a keyboard. Others capture data automatically, like a sensor.
When you answer an exam question, name the device, say what it is used for, then give a reason linked to the situation.
2.1 Input devices · The explanation · step 1 of 15 · part 2 of 2
What an input device does (continued)
2.1 Input devices · The explanation · step 2 of 15 · part 1 of 2
Keyboards and numeric keypads
A keyboard is used to type text and commands. Most use the QWERTY layout.
A concept keyboard has flat keys with pictures or words. Fast-food tills use them.
A numeric keypad has only numbers and a few keys. It is on ATMs, chip and PIN terminals, phones and the side of large keyboards.
2.1 Input devices · The explanation · step 2 of 15 · part 2 of 2
Keyboards and numeric keypads (continued)
| Device | Use | Advantage | Disadvantage |
|---|---|---|---|
| Keyboard | Typing documents, emails, data into forms | Fast, accurate entry of text for a trained typist; familiar to most users | Slow for people who cannot type; long use can cause RSI; takes up desk space |
| Numeric keypad | Entering PINs at an ATM, prices at a till, phone numbers | Faster than a full keyboard for numbers; small, so fits on a card terminal | Keys are small and can be hard to press; PIN can be seen by shoulder surfing |
2.1 Input devices · The explanation · step 3 of 15
Pointing devices
A pointing device moves a pointer (cursor) on a screen and selects things.
A mouse is moved on a desk. A touchpad is a flat pad on a laptop: you move a finger on it. A trackerball is like an upside-down mouse: you roll the ball and the device stays still.
| Device | Use | Advantage | Disadvantage |
|---|---|---|---|
| Mouse | Selecting icons and menus in a GUI; drawing | Faster to select options than using keyboard shortcuts; easy to use | Needs a flat surface; can cause RSI with long use |
| Touchpad | Pointing on a laptop | Built in, so no extra device to carry; works where there is no desk | Harder to control precisely than a mouse, e.g. for drawing |
| Trackerball | People with limited hand movement; control rooms; some medical equipment | Does not move, so needs less space and less wrist movement; easier for some disabilities | Not as fast as a mouse for most users; costs more |
2.1 Input devices · The explanation · step 4 of 15
Remote controls, joysticks and driving wheels
A remote control sends infrared or radio signals to a TV, projector or air conditioner from a distance.
A joystick controls movement in games and flight simulators. A driving wheel controls steering in driving games and car simulators.
| Device | Use | Advantage | Disadvantage |
|---|---|---|---|
| Remote control | Changing TV channel; controlling a projector or a multimedia system | Can be used from a distance, so the user does not need to move | Infrared needs a clear line of sight; small buttons hard for some people; easy to lose |
| Joystick | Games; flight simulators; controlling robot arms | Easier to control movement in any direction than with keys; feels realistic | Harder to use for selecting menus or typing |
| Driving wheel | Driving games and training simulators | More realistic than a keyboard, so training is more useful | Expensive; takes up space; only useful for one kind of task |
2.1 Input devices · The explanation · step 5 of 15
Touch screens and light pens
A touch screen is a screen you touch to select options. It is used on phones, tablets, ATMs, information kiosks and self-service tills.
A light pen is a pen with a light sensor. You point it at a screen to draw or select. It is rare now and is used in some design and medical work.
| Device | Use | Advantage | Disadvantage |
|---|---|---|---|
| Touch screen | Phones, ATMs, kiosks, self-service checkouts | Fast and intuitive, no training needed; no keyboard or mouse, so saves space | Screen gets dirty and scratched; limited options per screen; hard for some disabilities |
| Light pen | Drawing directly on screen; selecting on medical or design screens | More precise than a finger; no desk space needed | Can be tiring to hold up against a screen; not suitable for all screen types |
2.1 Input devices · The explanation · step 6 of 15 · part 1 of 2
Scanners, digital cameras and microphones
A scanner turns a paper document or photo into a digital image.
A digital camera takes photos and videos and stores them on a memory card.
A microphone turns sound into an electrical signal. Uses: video calls, voice recognition, recording.
2.1 Input devices · The explanation · step 6 of 15 · part 2 of 2
Scanners, digital cameras and microphones (continued)
| Device | Use | Advantage | Disadvantage |
|---|---|---|---|
| Scanner | Digitising old photos and documents; with OCR, turning print into editable text | Faster than retyping or redrawing; makes a digital backup of paper | Quality depends on the original; large image files |
| Digital camera | Photos for websites, ID cards, reports | Images can be checked at once and deleted; easy to transfer to a computer | High-quality images use a lot of storage; good cameras are expensive |
| Microphone | Voice recognition, video calls, voice notes | Faster than typing for many users; hands-free | Background noise affects quality; voice recognition makes errors |
2.1 Input devices · The explanation · step 7 of 15 · part 1 of 3
Sensors
A sensor measures a physical quantity, such as temperature, and sends the reading to a computer. The data is usually analogue, so an ADC converts it.
Sensors take readings automatically and continuously, day and night. A person does not need to be there.
2.1 Input devices · The explanation · step 7 of 15 · part 2 of 3
Sensors (continued)
| Sensor | Measures | Example use |
|---|---|---|
| Temperature | How hot or cold | Central heating, greenhouses, ovens |
| Light | Light level | Street lights turning on at dusk; phone screen brightness |
| Pressure | Force or weight | Burglar alarm mats; car airbags; checking tyre pressure |
| Moisture / humidity | Water in soil or air | Watering plants in a greenhouse; museums |
| Infrared / motion | Movement or heat from a body | Security lights; automatic doors |
| Sound (acoustic) | Noise level | Burglar alarms detecting breaking glass |
| pH | Acidity | Fish tanks; checking river pollution |
| Gas (e.g. CO2, oxygen) | Gas levels | Greenhouses; carbon monoxide alarms |
2.1 Input devices · The explanation · step 7 of 15 · part 3 of 3
Sensors (continued)
Advantage: readings are more accurate and more frequent than a person could take, and work in dangerous places. Disadvantage: a faulty sensor gives wrong data, and sensors cost money to install and maintain.
A sensor does not "control" anything. It only measures. The microprocessor decides and an actuator acts.
The explanation · 8 more steps
More on the lesson page
The lesson page has the rest of the explanation, step by step:
- What direct data entry means
- Card readers: magnetic stripe, chip and PIN, RFID
- OMR and OCR
- Barcode readers and QR code scanners
- Monitors, touch screens and projectors
- Laser, inkjet and dot matrix printers
- Plotters and 3D printers
- Speakers and actuators
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Quick quiz · 1 of 3
An advantage of an SSD over a hard disk is…
- A It is cheaper per GB
- B No moving parts, so it is faster and tougher
- C It has a bigger capacity
B. No moving parts, so it is faster and tougher
Hard disks still win on cost per GB.
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Quick quiz · 2 of 3
A memory card in a camera is…
- A Solid state
- B Magnetic
- C Optical
A. Solid state
Flash memory, no moving parts.
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Quick quiz · 3 of 3
.csv is…
- A A picture
- B A web page
- C Comma-separated values: a generic data format
C. Comma-separated values: a generic data format
Any spreadsheet or database can open it.
Year 10 · ICT · Computer systems, devices and storage; document production · Lesson 3 of 5
Exit ticket
Answer on paper before you go. Then check.
A .pdf is used because…
A Anyone can edit itB It is the smallest fileC It looks the same on every computer
C. It looks the same on every computer Layout and fonts are fixed inside the file.
Zip compression is…
A NeitherB LossyC Lossless
C. Lossless Every byte comes back when you unzip.