1.2 Memory and Storage Flashcards
What is primary memory?
Memory built in computer to be accessed quickly
What does RAM store?
Operating system
Currently open applications
What does ROM store?
Bootstrap
BIOS
Define volatile :
Data is lost if device is turned off
What is an advantage of cache?
Fast processing
Closer to CPU
What is a disadvantage of cache?
Expensive
What is virtual memory?
Extension of RAM in hard disk
What are the advantages of virtual memory?
Saves money
Extra RAM space
Swapping
What are the disadvantages of virtual memory?
Slow
Shortens hard disk life span
What is secondary storage?
External, non volatile memory
Define optical memory :
Pits = 0
Lands = 1
Cheap
Portable
Define magnetic memory ;
Concentric circles
Magnetised and demagnetised
Cheap
Large capacity
Define solid state memory ;
No moving parts
Fast
Large capacity
Portable
Durable
Reliable
What are the characteristics of secondary storage?
Cost £/GB
Capacity
Speed
Reliability
Durability
Portability
Define lossy compression :
Data lost
Reduces bit depth
Very compressed