Module 1.2 Flashcards
What is the difference between data and information? Express your answer in terms of the role of the computer.
Data refers to raw, unprocessed facts. Computers take data and process it into useful information.
Give two destinations for output, or ways in which output can be used.
Output can be sent directly to storage.
Output can be communicated directly to other computers.
Output can be used as input for other programs and computer systems.
Output can be used to control equipment or devices.
Why is the memory (RAM) of an ICT device so important in terms of processing?
Processing can only take place when the software and data is loaded into the memory (RAM) of the ICT device.
Give two types of processing that one might perform on data.
Searching, sorting, comparing, calculating, etc.
Give two ways in which sensitive data can be protected, besides physically restricting access to the data.
Encryption and backups (stored off-site).
Would you classify a touch screen as an input device or as an output device? Motivate your answer.
It is both. Input, as it allows the user to provide input by touching the screen, and output, as it displays output as a normal computer screen does.
Give the main advantage and the main disadvantage of using a wireless keyboard or mouse as opposed to a wired one.
A wireless keyboard/mouse clears clutter from the desk or work surface.
A wireless keyboard/mouse can be inconvenient as you can’t use the device if the batteries are flat and you don’t have spare batteries.
Give three reasons why a touch screen device is often used in restaurants.
Quicker/easier and more accurate to input data, especially with a fixed selection of options. Saves space as it serves the function of both a mouse and a keyboard.
It is easy and intuitive to use and requires very little training.
Give the two main reasons why one should buy an ergonomically designed keyboard.
Comfort / ease of use.
Safety aspects such as reducing the risk of RSI (Repetitive Strain Injury) / CTS (Carpal Tunnel Syndrome).
State where you typically find a touchpad and give two advantages of using a touchpad over a mouse.
A touchpad is a hardware device built into laptops / portable computers.
As the name ‘laptop’ suggests people often use these machines on their laps where there is no space or way to use a mouse.
Having a touchpad also means there is one less item to carry around / potentially forget.
Give five general advantages of having hard copies scanned and saved in digital format in the context of a business or office environment.
One can store and share documents digitally which means that less paper and ink are used, which is beneficial to the environment.
Large documents that consist of many pages can be scanned and collated into a single digital file (usually a PDF).
Scanned copies need less physical storage space – a hard drive can hold thousands of documents.
It is faster to use a scanner and OCR software than retyping a document.
Scanned copies can be shared electronically rather than through the slow physical process of mail or courier.
Give two scenarios where it is preferable to use RFID tags instead of conventional barcodes.
E-tolling/toll roads, stock control in shops and warehouses, pet tracking, access control systems, etc.
Your sister has a 10 MP digital camera. Explain how the term ‘resolution’ relates to this specification.
Each digital picture is made of small ‘dots’ or pixels. The resolution of the image refers to the number of horizontal and vertical pixels in the image. Multiply the two and you get the total number of pixels – in this case 10 MP or 10 mega (million) pixels.
List and describe four factors, other than the resolution, that the quality of an image taken with a digital camera depends on.
Colour depth – the number of bits used to represent a colour.
Sensor size – the bigger the sensor in a camera, the better the quality of the image. ISO rating (the camera’s sensitivity to light).
Using optical rather than digital zoom.
Do scanners and digital cameras uses the same units to measure resolution? Motivate your answer.
No, digital cameras use (mega) pixels to measure resolution and scanners measure resolution in terms of the number of dots they can scan per inch (dpi).
Explain what the specifications aspect ratio, the contrast ratio and the refresh rate refer to
The aspect ratio is the relationship between the width and height of the display e.g. 16:9 or 16:10 displays.
The contrast ratio is the relationship between the darkest black and the brightest white. Low contrast ratios produce soft, muddy images.
The refresh rate refers to how often (how quickly) the screen display is refreshed. The higher the refresh rate, the better the display.
Suppose you switch on your computer and there is no display. Give two troubleshooting steps you can take to try to solve the problem.
Check that the monitor is switched on and receiving power.
Check all the connections.
If the monitor can accept multiple inputs, check that it is set to display the correct input.
Give four specifications you might consider when purchasing a new printer, besides the type of printer, the colour factor, the cost and the warranty.
Speed Resolution
Cost per page
Paper size that can be used
Wireless capability / Has a network port
Inkjet printers are generally cheaper to buy than laser printers, but they have some disadvantages compared to laser printers. Give three of these disadvantages.
Higher running costs than laser printers.
Slower printing speeds than laser printers.
Generally, the text print quality is not as good as that of laser printers.
How does a 3D printer differ from other types of printers, in terms of what it can print?
It creates a physical, three-dimensional object.
What does it mean when we say storage is non-volatile compared to RAM which is volatile?
It means that storage retains its contents even when the power is switched off. RAM loses its contents
if it is not constantly supplied with power.
Why does storage always have to have a larger capacity than RAM?
Only programs and data that need to be processed need to be loaded into RAM.
Storage must permanently store all your programs and data, even when the computer is switched off.
Give four reasons why an external hard drive is better for backups than using optical discs (CD and DVD).
Ease of use – they can just be plugged into a USB port and used. Higher speed – faster than optical media.
Much larger capacity than optical media.
Reliability – more reliable than optical media.
Name two types of port to which you can connect an external hard drive.
USB, Thunderbolt
Give one advantage and one disadvantage of a 2.5” drive compared to a 3.5” drive.
2.5” drives can get their power from the computer using the connection cable, whilst 3.5” drives need a separate power supply.
2.5” drives generally have smaller capacities than 3.5” drives.
Give five reasons why flash drives have largely replaced optical discs (CD and DVD).
They provide much faster data access.
They are ‘industry standard’, i.e. useable with all operating systems and most devices, provided the devices have USB ports.
USB ports are found on virtually every type of computer or device, whereas a CD or DVD needs an optical drive.
They have a much larger capacity than optical media.
They are more reliable (CD and DVD discs can easily get scratched or damaged). They are easier to use in terms of adding and deleting files.
They are physically smaller and easier to carry around (e.g. fit into a pocket).
Give two reasons why many companies prohibit (stop) their employees from bringing any portable devices (such as flash drives) to work with them, besides being ‘distracted’ by them.
Their small size, large capacity and ease of use means that they make it easy for people to pirate media, copy and steal data or install illicit software on computers that are not their own.
Give two advantages and two disadvantages of an SSD over a traditional (mechanical) hard drive.
Advantages:
● SSDs are much faster than traditional hard drives.
● SSDs have the advantage of no moving parts and therefore can’t be damaged easily by being
moved whilst in use.
● SSDs are much more energy-efficient and run more quietly than traditional (mechanical) hard
drives.
Disadvantages:
● SSDs are more expensive than traditional hard drives.
● SSDs generally come in smaller capacities than traditional hard drives.
Why is a cellular connection not always as reliable as a fixed line connection?
Cellular internet connections depend on the coverage and strength of the cellular signal.
Give one reason why fibre is more reliable than ADSL.
Not affected by electronic noise / interference / EMI.
(Electromagnetic interference (EMI) is unwanted noise or interference in an electrical path or circuit caused by an outside source. It is also known as radio frequency interference.)
Give three other problems that might cause a printer not to print at all.
The wrong printer is selected in the print dialog box.
The print job has been paused.
The printer may be jammed (page stuck).
There is no ink/toner or paper left, etc.
Briefly explain what a keylogger is and why it is so dangerous.
Keyloggers are a type of software (falling under the category of spyware) that can track and record your keystrokes and even track what your mouse is doing and the places where you click on the screen.
In this way the person who installed the software can monitor what you are doing and also obtain your passwords, etc. without your knowledge or permission.
Give five benefits of using Radio Frequency Identification (RFID) tags as opposed to barcodes in a warehouse environment.
Can be read at a distance wirelessly.
Can be scanned more quickly.
Less labour intensive to work with.
Allows items to be located within the warehouse. Can include more information (e.g. than just a price).
Why might installing software from a DVD be a problem on a newer laptop computer?
In order to save space and reduce power consumption, many newer laptop computers are not equipped with an optical drive.
Give two examples of GUI types of controls that can be used to minimise the amount of data a user has to enter in a program (and reduce the risk of typing errors).
Drop-down lists, date pickers (to choose a date from), spin edits, check boxes, radio buttons, etc.
Why would it perhaps not be a good idea to use a high-resolution webcam when you are using Skype to communicate with a friend overseas
High-resolution images use a lot of bandwidth/cap.
Give two reasons why one might choose to use a portable hard drive, rather than a portable SSD, to store backups.
SSDs are (much) more expensive, per gigabyte, than portable hard drives.
SSDs have a smaller capacity than portable hard drives (although their capacities are increasing).
What is an example of input?
Keyboard
Mouse
Touchpad
Touch screen
Scanner
Digital camera
What is an example of output?
Screen
Printer
Data projector
Touch screen
Speakers
What is an example of processing?
CPU
RAM
What is an example of storage?
Hard drive
SSD
Flash drive
Optical media
What are the advantages of a keyboard?
Fastest way to enter text
Easy to learn and use
What are the limitations of a keyboard?
Not designed to be used with a GUI interface
Takes up space
Can be difficult to use for some people
Keyboard skills require
What are the factors to consider when buying a keyboard and the troubleshooting steps
Factors – buying decisions
Ergonomic considerations
Wireless vs cabled
Troubleshooting
‘Sticky’ keys: clean with damp cloth / small brush
Wireless keyboard not responding: batteries / dongle / port
Wired keyboard not responding: disconnect and reconnect
What are the limitations of a mouse?
Best used at a fixed workplace with a suitable surface area
Entry-level mouse not very precise or accurate
What are the advantages of a mouse?
Easy‑to‑learn
Effective way to interact with GUI
What are the factors to consider when buying a mouse and the troubleshooting steps
Factors – buying decisions
Ergonomic considerations
Wireless vs cabled
Troubleshooting
‘Sticky’ mouse: use a clean, smooth, non‑reflective surface
Wireless mouse not responding: batteries / dongle / port
Wired mouse not responding: disconnect and reconnect
Final solution: reboot computer
What are the limitations of a Touch screen?
Not as easy to use as a physical keyboard
Some need extra pressure to work
Quality of the ‘touch experience’ depends on OS being used
Screen display area reduced
Not easy to use for certain tasks
What are the Advantages of a Touch screen?
Serves as both mouse and keyboard
Natural input, such as drawing and gestures
Intuitive interactions, e.g. swiping, pinching, expanding
Easy to use, intuitive, requires little training
What are the advantages of a Touchpad?
User does not have to carry an extra device such as a mouse
Same actions as mouse, without need for desk or extra surface area
What are the limitations of a Touchpad?
Not as accurate or precise as a mouse
Can be difficult to use with drag and drop operations – and because of limited size of touch pad itself
Cannot be repositioned in relation to screen for ease of use
What are the uses of a scanner?
Capturing images from paper sources
Capturing images of text for conversion to editable text with OCR software
Reading barcodes
What are the advantages of a scanner?
Easy to convert documents into digital format
OCR text conversion faster than retyping
Easy to convert old film photos into digital format
Benefits environment as less paper and ink are used
What are the limitations of a scanner?
Quality of scanned image depends on quality of the original doc / image
Affected by dirt or fingerprints on glass, or dust on sensor
Books difficult to scan with flatbed scanners
Can be slow
what do you do when you need to troubleshoot a scanner
Errors in image size or quality: check settings of the scanning software
Non‑responsive scanner: check if
switched on
plugged in
properly connected to USB port
lock switch is off
What are the advantages of a digital camera?
Photos already in digital format
Easy to use
Doesn’t cost money to take photos
View photos instantly
Photos are easy to share
GPS feature will include location in metadata – geo-tagging
What are the limitations of a digital camera?
Photos are easy to lose along with the device
Quality of photos depends on quality of camera
What are the factors to consider when buying a digital camera and the troubleshooting steps
Factors – buying decisions
Resolution
Number of horizontal and vertical pixels in the image
Minimum 300 dpi for printing
72 dpi suitable for on‑screen / web display
Image quality depends on:
Colour depth – the higher, the better (32 bits currently the maximum)
Sensor size – the bigger, the better
ISO rating – the camera’s sensitivity to light (higher is better)
What are the advantages of a Webcam?
Cheap
Small
Often built into portable computers
Video calls allow you to see the person you are talking to
What are the limitations of a Webcam?
Very low resolution – doesn’t create good images
Must be connected to an ICT device to work
What do you do when you need to troubleshoot a webcam
If webcam is unresponsive, check that it is
plugged in properly
switched on
selected as the current camera to be used by the software
Webcam software (or operating system utilities) can be used to test functionality and to troubleshoot problems
What are the advantages of a microphone?
Record verbal communication
Give voice commands
Add sound input to a computer
Use software to edit, analyse or manipulate sound
What are the limitations of a microphone?
Built-in microphones don’t generally provide high quality sound
Difficult to use in noisy environments
What are the Advantages of a monitor?
Immediate feedback to user
Allows for interaction between user and PC
Displayed content can easily be changed
Text can be enlarged for the visually impaired / high contrast used
Display options can be changed to suit user
What are the Disadvantages of a monitor?
Quality of display related to monitor size
Size of the monitor limits portability
Output difficult to share (unless it is a projector)
Image quality affected by natural lighting of environment
What are the factors to consider when buying a monitor and the troubleshooting steps
factors
Resolution and image quality
Image quality depends on horizontal and vertical pixels, aspect ratio, colour depth, pixel density, refresh rate and contrast ratio.
TROUBLESHOOTING STEPS
Colours faded, too strong or muddy, or image too bright or too dim- Adjust settings (contrast, brightness, etc.)
Image ‘blocky’ or stretched- Change resolution to recommended / best setting
Image tinted a colour- Connector or cable is damaged – check and replace if necessary
No display- Monitor not receiving power / cable not in properly / computer not switched on / monitor faulty – check, swop or replace
What are the Advantages of speakers and headphones?
Headphones – listen to sounds without disturbing others around you
Headphones – listen to sounds on mobile devices ‘on the go’
Speakers – a group of people can hear sound at the same time
What are the Disadvantages of speakers and headphones?
Sound quality depends on quality of peripheral
To play loud enough for a group – need additional audio equipment, e.g. an external amplifier
Use of speakers can cause distraction / be annoying
What are the troubleshooting steps for speakers and headphones
If no sound from speakers or headphones
might be plugged into wrong jack (e.g. microphone jack)
speakers that need power might not be plugged in, or switched off
computer’s sound settings may be low or on mute
computer might be set to use the wrong sound output device
What are the Advantages of printers?
Laser
Speed
High quality text
Low running costs
Inkjet
Cheaper to buy
Best quality photographic printers
3D Printers
3D printing is much cheaper than conventional manufacturing methods.
3D printing technology enables home users to have access to machines that can build 3D models.
Parts needed for a project can be made ‘on-demand’.
Print a model of a product that does not yet exist.
Customers can inspect a physical model before it is manufactured.
Ordinary users can easily create 3D objects.
Companies may use it in the manufacturing process as it may be more efficient or cost effective.
What are the Disadvantages of printers?
Laser
Not the best for printing good quality colour photos
Toner not absorbed by the paper – can wear off
Inkjet
Higher running costs
Slower printing speeds
Text print quality not as good as that of laser printers
What are the troubleshooting steps for printers
Printer is unresponsive
Not plugged in / power is off
Not properly connected to computer
Wrong printer selected in print dialogue box
Content incorrect and does not make sense
Wrong printer driver installed
Poor picture quality
Printout faded or irregular – low on ink or toner
Wrong type of paper
Network printer not working
Network settings of printer or computer are wrong
Paper stuck in printer – remove manually
what are some factors when considering to buy a printer
Speed – pages per minute (ppm)
Colour – separate cartridges for colours are better
Resolution – higher resolution is better (but uses more ink / toner)
Cost per page
Paper – type of paper is important, also paper size (e.g. A4, A3)
What are the Advantages of 3D printing?
Print out prototypes of new designs
Print ‘once-off’ custom parts – more affordable
Print tools and parts as and when needed
Create newer, revolutionary designs
What are the Disadvantages of 3D printing?
Expensive (but generally work out cheaper in the long run)
Can be slow, noisy, smelly
Need a lot of control and attention to work well
What are the Advantages of a Data Projector?
Allows the display to be viewed by a large group of people
What are the Disadvantages of a Data Projector?
Resolution of images not as good as those of high quality display monitors
Normally limited to 4:3 aspect ratio
Lower contrast ratios result in muddier images with lower colour quality
Images not as bright as those of high quality display monitors
What are the Advantages of a Hard drive?
Larger capacity than RAM
Cheaper per GB than RAM
Store data and programs when device is switched off
What are the Disadvantages of a Hard drive?
Easily damaged if improperly handled
Comparatively slow, as it operates on a mechanical basis
What are the troubleshooting steps for Hard drives
Storage may be nearly full
Delete or remove files
System seems slow and unresponsive
Use disk defragmentation utility to rearrange files on disk – so scattered parts of files can be put back together (this does NOT free up space-only makes your PC faster)
Files are corrupted
Because computer did not shut down properly, or programs crashing
Right-click on disk Properties Tools Check
What are the Advantages of a External Hard drive?
Large capacity
Portability
Ease of use
High speed
Reliability
Provide extra storage (without need to open computer)
What are the Disadvantages of a External Hard drive?
Not as small as a flash drive
As vulnerable to improper handling as internal hard drives
Can drain battery power on laptop
What are the Advantages of a Flash drive?
Portability
Fast data access
Cheap
Larger capacities than optical media
Industry‑standard use
Reliability
Easy to use (adding and deleting files)
No need for external power source
May include embedded security
What are the Disadvantages of a Flash drive?
Easy to lose, easily stolen
More expensive per GB than hard drives
Lower capacities than newer hard drives
What are the Advantages of Optical Media?
Affordability
Portability
Industry‑standard use
What are the Disadvantages of Optical Media?
Slow
Easily damaged
Relatively small capacity (700 MB for a CD,4.7– 8.5 GB for a DVD)
Not as easy or intuitive to write to as flash drives
Laptops are increasingly designed without optical drives
What are the Advantages of a cellular modem?
Easy to install and use (plug into USB port)
Small – portable internet access on any computer
3G/4G network is fast
What are the Disadvantages of cellular modem?
Easily lost or stolen
What are the Advantages of a ADSL and Fibre Router?
ADSL router – make and receive phone calls and be connected to internet at same time
Includes built-in switch
WiFi capability of router – can connect devices wirelessly
What are the Disadvantages of a ADSL and Fibre Router?
ADSL – you need a landline
Fibre – physical cable connection to an existing fibre network
ADSL cable theft a problem because of the copper content
why HDMI output is better than VGA output.
Better image quality/video/audio
The signals are digital (not analogue)
HDMI cable carries video AND audio
