1.2 Memory and Storage Flashcards
Give 2 examples of primary storage
RAM
ROM
Describe RAM
Random access memory
Volatile- temporary
Stores programs currently running
Describe ROM
Read only memory
Non volatile
Stores boot up program
Virtual memory
When all RAM is full,
HDD drive secondary storage used as extension
Slow,
Why do we need secondary storage
To save data long term
Non volatile
Describe optical storage
DvD
Low capacity
Cheap
Portable
Slow access speeds
Describe magnetic storage
Large capacity
Slow access speeds
Not portable
Mid access speeds
Describe solid state storage
Portable
Fast access speed
high capacity
Expensive
Hoe many bits in a nibble
4
How many bits in a byte
8
How many kilobytes in a megabyte
1000
Equation for sound file size
Bit depth x duration x sample rate
Image file size equation
Colour depth x height x width
Text file size equation
Bits per character x characters
Ascending powers of 2 for binary
1 2 4 8 16 32 64 128 256
How to convert denary to hexx
Divide the number by 16
Allocate apohabet corresponding if above 10
Denary - the remainder
State the 2 character sets
Ascii
Unicode
What does metadata store
Additional Image info eg size and location
How must analogue sounds be stored
Binary
Describe Lossy compression
Unrequited data removed from file
Quality reduced
Describe Lossless compression
Uneeded data removed from the file
added back before being used again
