1.2.3 units

Question 1

why does data have to be stored in a binary format?

Answer 1

data needs to be stored in binary format because computers only have 2 states: on/off, true/false, yes/no, 1/0

All data that we want a computer process needs to be converted into a binary format to be processed by a computer.

binary = base 2 
denary = base 10

Question 2

bit

Answer 2

a bit is a 1 or 0

it is the smallest unit of data a computer can store

Question 3

nibble

Answer 3

4 bits

Question 4

byte

Answer 4

8 bits or 2 nibbles

example: keyboard characters

Question 5

kilobyte

Answer 5

1 kB = 1000 bytes

example: document file sizes

Question 6

megabyte

Answer 6

1 MB = 1000 kB

example: measure storage space on a CD

Question 7

gigabyte

Answer 7

1 GB = 1000 MB

example: hard drive sizes

Question 8

terabyte

Answer 8

1 TB = 1000 GB

example: over 300 hours of videos

Question 9

petabyte

Answer 9

1 PB = 1000 TB

example: 315 million photos

Question 10

calculating sound file size

Answer 10

sound = sample rate X duration (s) X bit depth

Question 11

calculating text file size

Answer 11

text = bits per character X number of bits

Question 12

calculating image file size

Answer 12

image = colour depth X image height X image width