Computers, part of your life - Grade 11: Module 1.2 Input and Output

Flashcards covering input and output devices, specifications, assistive technology, and health considerations from Module 1.2.

What is the role of input in the information processing cycle?

Input is the first step in the cycle, providing software with instructions on what to do next and data that must be processed.

What is biometric input and why is it used for access control?

Biometric input involves capturing unique biological features of a person (such as body parts, voice matching, or gait). Defeating biometric security is difficult because it is tied to a single person, making it a secure alternative to typed passwords.

What is a barcode and how is it processed by a scanner?

A barcode is a number or alphanumeric code represented by black and white stripes on packaging or documentation. A scanner reads the stripes to identify a number that corresponds to a field in a database.

What are the main advantages of scanning a barcode over typing data manually?

Scanning a barcode is faster, more efficient, and more accurate than reading and typing, and it allows additional information about the item to be looked up automatically.

How do microphones function as input devices beyond recording sound?

Microphones allow live processing of sound for voice recognition, enabling users to enter data, give commands, and interact with cloud-based AI assistants like Alexa through spoken conversation.

What two hardware components combine to create a touch screen input device?

A touch screen combines an LCD screen with a transparent touch-sensing film that senses the coordinates of a finger or stylus and clicks when pressed down.

What is a virtual keyboard and in what situations is it commonly used?

A virtual keyboard is a software-created keyboard on devices without physical keys. It is commonly used as the default input on smartphones/tablets, by people with disabilities, or where physical space is limited, such as POS systems in restaurants.

How do wireless input devices connect to a computer?

They use radio waves to connect, either via a USB dongle plugged into the computer (establishing a private WiFi connection) or via built-in Bluetooth pairing.

What are the three main purposes of output in computing?

Output serves to provide the user with feedback, provide a permanent or non-electronic copy of processing results, and allow transmission of data between computing devices.

What is colour depth and how does it impact image quality?

Colour depth refers to the number of bits used per pixel to represent a colour. The greater the colour depth, the more accurate and realistic the images appear.

How do RGB channels enable a pixel on a screen to display different colours?

A pixel is made up of three colour channels (Red, Green, and Blue). By setting each channel to a different level of brightness, the pixel can display a specific colour.

What is screen resolution and how does increasing it affect displayed content?

Screen resolution is the number of horizontal and vertical pixels a screen can display (e.g. $1920 \times 1080$). Higher resolution allows more detail to be displayed, but text and images become smaller.

What component determines a screen's maximum resolution setting in the Control Panel?

The maximum resolution setting depends on the graphics card used.

What is aspect ratio, and what is the standard ratio for most modern displays?

Aspect ratio is the ratio between the width and the height of the screen. Most modern TVs, monitors, and laptops have an aspect ratio of $16:9$, which suits elongated movie formats.

How are printer speed, resolution, and monthly duty cycle measured?

Speed is measured in pages per minute (ppm), resolution in dots per inch ($dpi$), and monthly duty cycle as the maximum number of pages printed per month without failure.

What advantages do laser printers offer over ink printers?

Laser printers are generally faster, more reliable (no nozzles to clog or ink to dry out), easier to maintain, cheaper to run for higher volumes, and better for black-and-white and general colour printing.

For what type of output are ink printers superior to laser printers?

Ink printers are much better for creating photo quality prints.

What input devices are present in an Automated Teller Machine (ATM)?

ATM input devices include a physical or on-screen keypad and buttons, card reader, touch screen, money counter, money deposit slot, and server communication links.

What output devices are integrated into an Automated Teller Machine (ATM)?

ATM output devices include a touch screen, a printer for receipts or transaction summaries, and a cash dispenser.

How does RFID technology differ from barcode scanning in POS systems?

RFID can scan items without requiring a direct line of sight, whereas barcodes must be in direct line of sight to be scanned.

Why do most supermarkets continue to use barcodes instead of RFID tags?

Barcodes are cheaper to produce, less complex to implement, and customers at checkout prefer seeing items scanned one by one.

What input and output devices are standard in Point of Sale (POS) systems?

Input devices include barcode scanners, RFID readers, operator keyboards, and card reader/NFC keypads. Output devices include cashier display screens and receipt printers.

What assistive device for visually impaired users is shown in this image, and how does it function?

A Braille display; it uses a line of small pins that raise or lower to spell out Braille characters that a blind user can feel to read the screen content.

What output adaptations are available for hearing impaired or deaf computer users?

Computers can use on-screen notices or flashing screens instead of sound, as well as devices that utilize vibration rather than audio.

What input device for users with motor control issues is shown here, and how does it work?

A trackball; it stays in place on the desk while the user rolls a large movable ball to control the on-screen pointer.

What health topic regarding sitting posture and device usage is illustrated in this diagram?

Ergonomics, which addresses how posture and device usage affect health, preventing sore neck, backache, headaches, and Repetitive Strain Injury (RSI).

What practical habits help prevent health issues and eye strain when working with computers?

Get up and move every hour, look away at other objects periodically, learn keyboard shortcuts, do joint exercises, keep headphone volume moderate, and adjust monitor settings to eliminate glare.