1. Input / Output
Input - An input is data that a computer receives. Computers only work with digital information. Any input that a computer receives must be digitised.
Output - output is the data you receive after completing a process (e.g. word process etc.). Output devices pass data to the user from a completed process.

2. Input Devices Keyboard Mouse Touch Screen
A keyboard is an input device that sends information about the keys you press. This is received by the computer and it displays the correct letter or number.
Mouse
The computer mouse is considered an input device. With a click of a button, the mouse sends information to the computer.
Touch Screen
A touchscreen is a flat surface with a sensitive panel directly on the screen that registers the touch of a finger as an input. A touchscreen allows the user to interact with a device without a mouse or keyboard and is used with smartphones, tablets and computer screens.

3. Input Devices Microphone Camera Barcode Scanner
A microphone can be used to input sound. The sound is detected by the microphone and an electrical signal is transmitted to the computer.
Camera
A digital camera becomes an input device when you connect it to a computer.
You can use it to upload information, such as photos and videos to your device.
Barcode Scanner
A barcode reader is an automatic input device which is used to scan or 'read' the barcode by using a visible red light. The reflected light is translated into digital data that is interpreted by the computer to identify the product and price from the database.

4. Input Devices RFID Reader Sensors
Used to read data without physical contact. Examples include the London Oyster Card System, where the card has a Radio Frequency Identification(RFID) chip.
Sensors
Sensors are used to detect physical quantities outside a computer such as light, temperature and pressure. They collect data automatically and usually at regular intervals. This data can either be transmitted immediately to the computer or it can be stored for a period of time and a batch of readings sent in one go.

5. Input Devices – For users with specific needs
Eye - Typer
This can be used by people who cannot use a hand or foot operated mouse and a conventional keyboard. A camera is mounted onto the computer and it is set to focus on the user's eye. The camera determines where the user is looking and monitors movements made by the eye. Mouse clicks are done with a slow eye blink.
Puff – Suck Switch
This kind of switch is excellent for someone with limited physical mobility. You simply suck or puff down the tube in order to activate a switch. The switch itself is connected to the computer. Specific software running on the computer can take this input and act on it in any number of ways.

6. Input Devices – For users with specific needs
Voice Input
A voice input device is a device in which speech is used to input data or system commands directly into a system. Such equipment involves the use of speech recognition processes, and can replace or supplement other input devices.
Joystick
Joysticks were originally used by pilots as part of an aeroplane's controls and the technology was developed to let computer gamers experience a more realistic game environment. You can move joysticks in many directions and the joystick tells the computer which direction it has been moved into. They also have one or more buttons whose position when pushed can be read by the computer. Joysticks can also be used for controlling machines such as cranes, trucks and powered wheelchairs.

7. Input Devices – For users with specific needs
Foot Mouse
A foot mouse / control can be used by a person who has limited or no use of their hands or arms. The foot mouse can be used to navigate through software programs and select things in much the same way as a conventional mouse. Most foot mice consist of two segments. One segment will be used to control the cursor, the second segment is used to click the mouse or to select shortcuts. Most foot mice include straps that help to hold the device in place on the foot during use. A long cable runs from the mouse and plugs into the computer via a USB port.
Braille Keyboard
A Braille keyboard is a specialist input device that allows the user to type and enter text or instructions for the computer in Braille

8. Output Devices Monitor Printer Speaker
A monitor (or screen) is the most commonly used output device.
Printer
Printers are another common output device. They are used to create a 'hard' copy of your work i.e. something that you can hold, hand to someone else or file away.
Speaker
Most computers are fitted with a small internal speaker which can produce beeping sounds to alert you if you make an error. Computers can also be fitted with a sound card (or chip) which will enable sound to be output through external speakers. These usually produce a much higher quality sound than the internal speaker.

9. Output Devices Actuators
An actuator is a type of motor that is responsible for moving or controlling a mechanism or system. It is operated by a source of energy, typically electric current, hydraulic fluid pressure, or pneumatic pressure, and converts that energy into motion.

10. Output Devices – For users with specific needs
Screen Reader
Screen Readers are intended primarily to assist individuals who are blind or otherwise visually impaired. These solutions include magnification software, screen reading programs, and braille translation devices. Screen readers, or screen review programs, are highly specialized applications that will read, sometimes with the help of a speech synthesizer, what is currently displayed on the screen. Other packages are specialized to read scanned documents, essentially turning the computer into a reading machine for printed documents.
Voice Synthesisers
Voice synthesisers solutions assist a user who is unable to articulate to communicate with others. Voice synthesizers, either hardware or software, can produce a variety of voices which are clearly understandable. The coupling of these devices with an on-screen keyboard and head-mounted activating switch can enable a severly disabled person to speak using a single switch. In addition, the combination with word completion software makes the system very efficient.

11. Questions
A supermarket self-checkout has a range of input and output devices. Identify these and state if they are input or output and what purpose they serve.
A patient in intensive care is connected to a number of computer systems. Identify which are input and which are output. Explain the purpose of each.
A physically disabled person is unable to use their arms effectively. Explain what devices could be used to interface with a computer system.

12. Questions
A supermarket self-checkout has a range of input and output devices. Identify these and state if they are input or output and what purpose they serve.
Input: keyboard on the register (To type in the GTIN code of a product if it doesn’t scan), barcode scanner built into the counter (to scan the produce), scale built into the counter (weigh the produce), portable bar code scanner (for heavy things still in the trolley) and the credit/debit card reader (scan your card and remove money). Output: The display on the register (to show you what you have bought), the paper tape receipt printer (to print out your receipt) and the display on the credit/debit card reader (to instruct you on what to do).

13. Questions
A patient in intensive care is connected to a number of computer systems. Identify which are input and which are output. Explain the purpose of each.
Output - A large display / monitor shows graphs of pulse, breathing, etc. A loud buzzer / alarm can be sounded if there is a problem to attract the attention of a nurse/doctor .A small printer can produce a hard-copy of the data
Input - Heart Rate Sensor is used to monitor the patients heart rate. A thermometer is an input device used to measure the temperature of the patient.

14. Questions
A physically disabled person is unable to use their arms effectively. Explain what devices could be used to interface with a computer system.
Microphones – input device to use voice commands
Speakers – output device to tell the user what to do
Foot mouse – input device to allow the user to control the computer
Monitor – output device to tell the user information