Section 2: Storage

Question 1

what is primary storage?

Answer 1

• main memory CPU can access very quick
• smaller in storage size
• RAM and ROM

Question 2

what is secondary storage? (3)

Answer 2

• larger in storage size
• slower
• used for long time storage; non-volatile

Question 3

what is volatile storage?

Answer 3

temporary data is lost whenever the power is turned off
eg RAM

Question 4

what is non-volatile storage?

Answer 4

saves the data even when not powered
data can be stored
long term
eg ROM

Question 5

why do computers need primary storage?

Answer 5

accessing primary storage is much faster than secondary storage devices

Question 6

what are the 2 types of primary storage?

Answer 6

RAM and ROM

Question 7

what is RAM?

Answer 7

volatile
stores all the programs currently running

Question 8

what is ROM?

Answer 8

non-volatile and can’t be changed
stores BIOS

Question 9

what is virtual memory?

Answer 9

if there is insufficient space in RAM, computer can use the HDD/secondary storage an an extension of RAM

Question 10

what are some storage characteristics i should know? (4)

Answer 10

capacity
durability
portability
cost
reliability

Question 11

what is a magnetic hard disk drive? HDD (4)

Answer 11

• larger capacity
• cheaper cost per GB than SSD
• slower access speed than SSD but faster than optical
• durable and portable

Question 12

what is optical storage? (4)

Answer 12

• low capacity
• not durable
• has the slowest access speed
• discs are very thin and portable

Question 13

what is a solid state storage? (5)

Answer 13

• most expensive cost per gb
• usually durable
• small size means portable
• high capacity and faster access speed

Question 14

why do computers use binary?

Answer 14

computer systems consist of billions of tiny transistors which are switches that only have 2 values 1/0
therefore data is represented dis way

Question 15

what is a kilobyte?

Answer 15

1000 bytes

Question 16

what is a megabyte?

Answer 16

1000 kilobytes
(1000 x 1000 bytes)

Question 17

what is a gigabyte?

Answer 17

1000 megabytes
(1000 x 1000 x 1000 bytes)

Question 18

what is a terabyte?

Answer 18

1000 gigabytes
(1000 x 1000 x 1000 x 1000 bytes)

Question 19

what is a petabyte?

Answer 19

1000 terabytes
(1000 x 1000 x 1000 x 1000 x 1000 bytes)

Question 20

what is the order of bits?

Answer 20

byte
kilobyte
megabyte
gigabyte
terabyte
petabyte

Question 21

what is an overflow error?

Answer 21

occurs when a binary value is too large to be stored in the bits available

Question 22

what is a character set?

Answer 22

is a table that matches together a character and a binary value
each character in a character set has a unique binary matched with it

Question 23

what does ASCII stand for?

Answer 23

American Standard Code for Information Interchange
1 byte - 8 bits

Question 24

what is unicode?

Answer 24

2 bytes - 16 bits
allows different languages to be represented; emojis, symbols

Question 25

what is compression?

Answer 25

to compress a file means to make its size smaller

Question 26

what are the benefits of compression? (2)

Answer 26

- files take up less storage - files can be transferred quicker

Question 27

what is lossy compression?

Answer 27

removes the data permanently, so the file can never return to it's original size

Question 28

what is lossless compression?

Answer 28

data is removed temporarily no reduction in quality text/softare files

Question 29

why is hexadecimal used to represent numbers instead of binary?

Answer 29

smaller easier to convert from binary to hex

Question 30

true or false: each character in a character set has a unique binary

Answer 30

trueee