Term 1- Secondary storage Flashcards
What are the 3 categories of memory
Primary, secondary, tertiary
Traits of Ram
Fast access, volatile, contains instructions and programs currently in use
Traits of ROM
Can’t be changed, non-volatile, contains essentials commands for computer to operate properly, includes POST and BIOS
POST stands for…
Power on system test
BIOS
Basic input output system
Virtual memory
Use of secondary storage as memory when RAM is full. Much slower than other types of memory
What are the 3 main types of secondary storage?
Magnetic, solid state, optical
What are the 6 dimensions to compare storage?
Cost per unit of storage, capacity, portability, speed, durability, resiliency
Describe how magnetic storage works
Disk contains tracks which are each divided into sectors. Disk heads mounted on mechanical arms read and write the data. 1’s and 0’s stored as magnetic polarities
Advantages(3) and disadvantages(3) of magnetic storage
Advantages:
-Cheap per GB of storage
-Large storage capacity
-Relatively fast access speeds
Disadvantages:
-Not very robust
-Life span of 4-5 years
-Not as fast as some other forms of media
Types of primary storage(4)
-RAM
-ROM
-Cache
-Register
Describe how optical storage works
Data stored as binary, disc spins at high speed, data stored in spiral that starts in centre and goes to edge, pits are 0’s hills are 1’s
Advantages(3) and disadvantages(3) of optical storage
Advantages:
-Cheap
-Easily portable
-Little physical space needed
Disadvantages:
-Less storage capacity
-Easily damaged
-Slow write speeds
Describe how solid state storage works
Very thin walls between compartments, electrons have a probability of being on either side of wall, electrons trapped in middle compartment, electrons escape in drain
Advantages(3) and disadvantages(2) of Solid state storage
Advantages:
-Very fast access speeds
-Very robust
-Physically small
Disadvantages:
-Expensive per GB
-Limited rewrite times
