1.1.3 Input, Output And Storage

Question 1

What is an input device?

Answer 1

An input device is one which can be used to put data and information into a computer

Question 2

What is an output device?

Answer 2

An ouput device is one which can be used to send information from the computer

Question 3

Give 4 examples of input devices:

Answer 3

Keyboard
Webcam
Magnetic stripe reader
Barcode reader

Question 4

What is a megnetic tripe reader used for?

Answer 4

It is used to read data from magnetic stripes on cards like debit and credit cards

Question 5

What is a barcode reader used for?

Answer 5

Used in supermarket checkouts and access control systems to read information from printed labels and cards

Question 6

What is a trackpad?

Answer 6

A tactile sensor typically found on a laptop or computer

Question 7

What does RFID stand for?

Answer 7

Radio frequency identification

Question 8

What are the differences between active and passive RFIDs?

Answer 8

Active RFID - physically larger and have a battery pack to power so that it actively transmits a signal which a reader can pickup
Passive RFID - No battery, rely on radio waves from a reader to power that chip

Question 9

What can RFIDs be used for?

Answer 9

Can be used in pets to identify the pets owner by storing a unique code which can be detected by a reader

Question 10

What is a RFID?

Answer 10

It consists of a small microchip transponder and an antenna

Question 11

What is a NFC?

Answer 11

A near field communication device

Question 12

What is the difference between NFCs and RFIDs?

Answer 12

NFCs are used for short range communication, which has important implications for physical access security, typically 10cms.
RFIDs can read up to 100 metres away

Question 13

What are linear barcodes?

Answer 13

The traditional barcode used in supermarkets

Question 14

What are 2D barcodes?

Answer 14

An example of a 2D barcode is a QR code which can store more information than a traditional linear barcode .

Question 15

How many characters can QR codes hold?

Answer 15

Up to 7000 characters meaning they can often only link to websites for example

Question 16

How do pen type readers work?

Answer 16

The tip of the pen is dragged across all the bars at an even speed.
The pen measures the intensity of the light reflected from the source and generates a waveform that is used to measure the widths of the bars and the spaces in the barcodes.

Question 17

What type of input sensors do cars have?

Answer 17

Video camera
Microphone
RADAR sensor
infrared sensor
Pressure sensor
Fuel sensor
A/C sensor

Question 18

How do optical storage devices work?

Answer 18

Optical devices are read from and written to using lasers.
Binary information is represented by portions of the disc which either reflect or scatter the incident laser light written in spiral tracks on the discs surface.

Question 19

What do pits and lands represent?

Answer 19

Pits represent a 0 and they scatter the light
Lands represent a 1 and they reflect light

Question 20

What are common types of optical storage?

Answer 20

CDs
DVDs
Blu-Ray

Question 21

What are 4 disadvantages of optical storage?

Answer 21

Easily damaged by scratches
Limited storage capacity
Relatively slow transfer speeds
Some can only be written to once

Question 22

What are 2 advantages of optical storage?

Answer 22

Low cost per MB
Small/light/portable

Question 23

How do magnetic storage devices work?

Answer 23

They store information magnetically by representing binary using two magnetic states: polarised and unpolarised.
If a portion is polarised, all the magnetic poles align and can be read by a read/write head passing over the region. if not polarised, the poles are randomly scattered and produce a different reading on the head. (0s and 1s)

Question 24

What are some examples of magnetic storage?

Answer 24

Hard disk drives
Magnetic Tape
Floppy disks

Question 25

What are 3 disadvantages of magnetic storage?

Answer 25

Slow data transfer speeds Less portable due to weight Not durable as it has moving parts ( arm uses an actuator to move)

Question 26

What are 2 advantages of magnetic storage?

Answer 26

High capacity Cheaper per GB

Question 27

How does flash storage work?

Answer 27

It makes use of silicon semiconductors forming logic gates NAND and NOR to store electrical charge in one of 2 states: high or low.

Question 28

What are 5 advantages of solid state storage?

Answer 28

Fastest read/write speeds Lightweight making it portable No moving parts so durable Silent in operation Consume less power meaning device using them has an extended battery life

Question 29

What are 2 disadvantages of solid state storage?

Answer 29

High cost per GB Have a limited number of read/write cycles

Question 30

What is a solid state hybrid drive (SSHDs)?

Answer 30

Combines the positives from both HDD and SSD. Significantly faster than a mechanical drive. The caching algorithm will store operating system and programs files in the solid state memory, offering high speeds when accessing cached files. As you use the drive and it learn which files should be cached speeds will gradually improve.

Question 31

What are characteristics of laser printers?

Answer 31

Offer high-quality, high-speed printing Uses powdered ink called toner Typically used for text-heavy documents Uses a thermal technique to bond the toner to the paper

Question 32

What are some characteristics of inkjet printer?

Answer 32

Work by spraying dots of ink onto paper to create an image Can produce photo-realistic images It can be cheaper than laser printers Slower than laser printers

Question 33

What can 3D printers be used for?

Answer 33

Create car parts Medical equipment Prosthetic limbs Prototypes Firearms Patented/copyrighted products

Question 34

What are actuators?

Answer 34

Motors which are commonly used in conjunction with sensors to control a mechanism

Question 35

What can actuators be used for?

Answer 35

Operating a window or a valve Starting or stopping a pump Turning a wheel Controlling devices in a smart home Opening a sliding door

Question 36

What are 8 input/output devices for disabled users?

Answer 36

Screen reader Eye typer Joystick Braille keyboard Voice input Puff-suck switch Foot mouse Voice sysnthesiser

Question 37

What is RAM?

Answer 37

Ram is a type of fast memory used to store data and programs which are currently open

Question 38

Why does RAM speed up the computers execution?

Answer 38

RAM has higher access speeds than even flash memory.

Question 39

What are 5 characteristics of RAM?

Answer 39

Volatile Fast access speeds More expensive per GB Larger memory than ROM Primary memory

Question 40

What is ROM used for?

Answer 40

Used to store information that needs to be permanently in memory like the boot program (bootstrap loader). After this some POST checks load the operating system

Question 41

What are 4 characteristics of ROM?

Answer 41

Smaller than RAM Holds the Bootstrap Loads the operating system Non-volatile

Question 42

What is virtual storage?

Answer 42

Virtual storage is given to storing information remotely so that it can accessed by any computer with access to the same system (for example over the internet)

Question 43

What are 5 advantages of virtual storage?

Answer 43

Backups automatically saved Data can be accessed anywhere with internet connection Data can be easily shared and worked on collaboratively Stored away from computer - incase of diaster not damaged Storage can be expanded as necessary

Question 44

What are 4 disadvantages of virtual storage?

Answer 44

Dependent on internet connection Privacy issues - data is held by a third party, putting trust in them to store your data One cloud storage company could be hacked Reliant on servers of the company providing connection