2.1.4 Data Representation Flashcards
(28 cards)
How many bits in a nibble?
4 bits are in a nibble
How many bits are in a byte?
8 bits are in a byte
How many byte in a kilobyte (Kb)?
1024/1000 bytes in a kilobyte
How many kilobytes in a megabyte (Mb)?
1024/1000 kilobytes in a megabyte
How many megabytes in a gigabyte (Gb)?
1024/1000 megabytes in a gigabyte
How many gigabytes in a terabyte?
1024/1000 gigabytes in a terbyte
What base number is binary?
Binary is a base 2 number system
What is ASCII? and what does it do?
Its the American Standard Code for Information Exchange. It turns the binary representation into a letter (based on the English alphabet)
What is Hexadecimal?
A base 16 number system used to make binary easier to understand, but has to be translated for computers to understand
What is hexadecimal used for?
Colour referencing (red, blue, green), assembly language, error messages and MAC address
What are the numbers for a hex table?
0 = 0 1 = 1 2 = 2 3 = 3 4 = 4 5 = 5 6 = 6 7 = 7 8 = 8 9 = 9 10 = A 11 = B 12 = C 13 = D 14 = E 15 = F
What are images made up of?
Dots aka pixels
Why is an image called a bitmap?
Because it’s a map of bits (pixels)
What does PPI stand for?
Pixels per inch
What does DPI stand for?
Dots per inch
How many colours can you have for 1 bit, 2 bits, 3 bits, 8 bits and 16 bits?
1 bit = 2 colours 2 bits = 4 colours 3 bits = 8 colours 8 bits = 256 colours 16 bits = 65,536 colours
What is meta data?
Image data that allows the computer to recreate the image from the binary data in the file
What must meta data contain?
Height and width in pixels, colour depth in BPP(bits per pixel)
What is analogue?
Made from a variation of dynamics and frequencies and records continuously
What is sample rate?
The number of audio samples captured every second
What is bit depth?
The number of bits available
What is bit rate?
The number of bits used per second/kilobytes per second
What is audio stored in?
Binary
Why isn’t computer recorded sound pure?
The sound has been digitized
