1.1.3: Input/Output + Storage

Question 1

Input and Output

Answer 1

Input: used to put data in

• keyboard, webcam

Output: used to send info from computer

-speakers, printers

Both: Touchscreen

Question 2

Optical Storage

Answer 2

• read from + write to using lasers
• binary info represented by portions of disc –> refects/scatter the laser
• pits and lands
• Pits scatter the laser (represent 0s)
• Lands reflect the laser (represent 1s)

Question 3

CDs

Answer 3

• compact disc
• used to store small quantities of info
• audio files, text and digital images
• small, thin and light - very portable
• can be scratched, limited storage and slow tansfer speed
• CD-R : written once
• CD -RW : written more than once
• CD - ROM : written in production then only read from

Question 4

DVDs

Answer 4

• Digital Versatile/Video Disc
• Higher storage than CDs
• Storing videos

Question 4

Blu - ray

Answer 4

• more than 5x more storage than DVDs
• storing higher resolution films

Question 5

Magnetic storage

Answer 5

• store info magnetically - 2 magnetic plates: polarised + unpolarised
• both states represent 1 and 0 –> binary

Question 6

hard disk drive (HDD)

Answer 6

• high capacity (500GB - 5TB)
• rotating magnetic platters at high speeds under read/write head on a actuating arm –> allowing access to any part of platter
• most HDDs stack platters to maximise storage
• slow data transfer, can be damaged due to moving parts

Question 7

magnetic tape

Answer 7

• long stretches of tape pass through readers - checking polarity , reading off binary
• quite bulky –> replaced by ROM cartridges

Question 8

floppy disk

Answer 8

• thin magnetic disk enclosed in plastic
• very portable –> thin, low weight
• 1MB –> 200MB

Question 9

Solid State Drive (SSD)

Answer 9

• extremely light + portable
• less prone to damage –> no moving parts
• high data transfer rates
• costly + limited lifespan

Question 10

RAM and ROM

Answer 10

• types of primary storage
• used by computer’s OS to run computer
• store info like code instructions +files which are required by running programs

Question 11

Random Access Memory (RAM)

Answer 11

• fast main memory
• stores data + programs computer currently uses
• speeding up execution time
• higher access speed than flash memory
• more expensive per GB than secondary storage
• Volatile –> loses info when the power is lost
• not used for personal files –> temporary storage instead

Question 12

Read Only Memory (ROM)

Answer 12

• cannot be modified
• useful for storing fixed sequences - computer’s start-up
• non-volatile –> data is retained even when power is off

Question 13

Virtual storage

Answer 13

• storing info remotely –> accessed by any computer with access to same system
• Google drive, Microsoft OneDrive, officed/school network storage
• More popular –> convenience of files being ‘in the cloud’
• limitations of user’s network speeds + high costs

Question 14

Flash memory

Answer 14

• fast + compact
• uses silicon semiconductors –> logic gate NAND + NOR –> store electric charge –> high/low which represent binary values True + False
• small qunatities –> NOR
• large quantities –> NAND
• erased + reprogrammed electronically
• non-volatile
• more expensive than other methods of storage like magnetic + optical