Secondary storage and storage devices

Question	Answer
Explain the need for secondary storage	Because RAM is volatile, data must be stored on secondary storage devices so it is not lost when the computer is switched off.
What is optical storage? Give examples	Uses light from lasers to read and write data on discs CDs and DVDs
What is magnetic storage?	This uses stacks of non- removable discs coated with magnetic materials
How does magnetic storage work?	- The disks spin and a read-write head moves across the discs - Electro-magnets in the read-write heads read and write the data
List examples	Hard drive and magnetic tape
What's solid state storage?	Where data is written and erased electronically so there are no moving parts
More info about SSS	- Faster to read/write than magnetic and optical - Writing, erasing and rewriting causes determination - Therefore, solid state storage is not used for critical systems
Give examples of solid state storage	Memory cards and USB flash drives
List considerations when picking a storage device	-Capacity -Portability -Reliability -Durability -Speed

Resource summary

	Created by Mel Hughes about 8 years ago