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RAM AND ROM is the main memory

RAM- random access memory

Volatile memory-temporary memory

RAM requires power to retain data and information- or RAM will lose data

RAM is slower than the cpu cache but alot faster than secondary storage

ROM- read only memory

tells the cpu how to boot up

ROM is non -volatile

non- volatile memory is permanent memory, keeps its contents without power

rom can only be read to not written to

these instructions are called the BIOS (basic input output system)

this tells the cpu to

perform self check ups

set up the computer

test the memory is working ok

see what hardware is present

copy the os(Operating system) into the RAM

Storage

3 tiers of storage:

Primary storage - refers to the memory areas thats the CPU can access very quickly (cpu registers cache rom ram)

secondary storage- where all the data is stored when not in use.

tertiary storage - used for storing data for long term purposes.mainly used for archives and back ups

things to consider for secondary storage

capacity

speed

portability

durablility -how robust is it

reliability

magnetic hard disks

hard disk drives- is made up of a stack of magnetised metal disks spinning at a rate between 5400-15000 rpm (revolutions per minute)

data is stored magnetically in small areas called sectors within circular tracks

solid state drives -SDD (storage devices) with no moving parts

faster read;/write times than hard disk drives

type of flash memory

ssd much quicker times booting up and opening programs and files

hybrid drives which use solid state storage for the operating system and programs and a hard disk for data

advantages of HDD

cheaper

high capacity

longer read/write life

advanages of solid state drives

faster

dont need defragmenting

shock proof

silent

optical discs

CD

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