1.2 storage Flashcards
secondary storage
non volatile, high capacity, slow access storage
how does optical storage work
holds data using pits burned into a plastic surface read by a laser beam
optical storage examples
CD, DVD, bluray
optical storage advantages and disadvantages
cheap, and lightweight, but cannot be wiped and rewritten
how does magnetic storage work
holds datât usine grains of magnetised material
magnetic storage examples
hard drive, magnetic tape
magnetic storage advantages and disadvantages
high capacity but big, heavy, not durable
how does solid state storage work
holds data using electrons trapped in solid matter
solid state storage examples
USB, SSD, SD card
solid state storage advantages and disadvantages
small, light, high capacity but expensive
cloud storage
storage accessed through internet connection, held remotely on a large computer owned by a company.
multimedia
digital recordings of sounds and images
factors effecting image
resolution - number of pixels
colour depth - how many colour codes
metadata
additional data alongside an image
factors affecting sound recording
sample rate - how frequently sound is sampled
bit depth - how many sound codes used
what are sound recordings measured in
hertz per second
how do sound waves reflect the recording
stored as number codes
amplitude - volume
wavelength - pitch
character set
set of characters and their codes eg ascii or unicode
order of file size
Byte
KB
MB
GB
TB
PB
calculate text file size
number of characters x bits per character
calculate image file size
resolution x colour depth
