Dta Representation Flashcards
What is a Bit Nibble Byte Kilobyte Megabyte Giga byte Terabyte
Bit is a BInery digiT, 1-0 Nibble is four bits A byte is 8 bits Kilo byte is 1024 bytes Mega byte is 1024 kilobytes Gigabyte is 1024 mega bytes Terabyte is 1024 giga bytes
How to convert denery into hex
Work out how many 16 are in the denery number. This is the first number, then the remainder is the second number. E.g. 182 = B6 as 182/16 = 11 remainder 6. 11 = B, 6 = 6
What is ascii
American standard computer code for infomation exchange. Every key on a keyboard has its special ascii 7 bit number so a computer can understand it
What is Unicode
Similar to Sacco but is in 16-32 bit so can store way way more different keys such as ones for Russian, japanese, Korean etc
What is a vector images
An image made of scaledble shapes so when it is enlarged or reduced, no quality is lost or gained
What are pixels
A picture element that makes up non vector images, when the image is enlarged, quality is lost as resolution stays the same
What is resolution
The pixel dimension of an image
What is colour depth
The amount of bits of memory a pixel uses, e.g. 8 bit pixels
What is meta data and what does it store
Data about the files such as last edited, file size, first made, file type
How is sound converted to digital
Analogue sound is received by microphone and converted to analogue electrical signals
The amplitude of the signal (height of sound wave) is measured at regular intervals (sampling, like taking images at reg intervals for video)
These values are rounded to a level
These levels are stored as digital numbers in a file
How is sound recording affected
Sample resolution, how closely the rounded level is to real sound. E.g. Rounded to 1 dp is lower than to 2dp as more accurate
Sampling rate, how many samples are taken per second, how small the interval between them is
What is the difference between data and information
Data is memory used up, infomation is useful data
