1.2 memory 1.3 storage

1.2 memory 1.3 storage

1. why is it needed ?

   • secondary storage
     • charecteristics
       • cost
       • reliability
       • durability
       • portability
       • speed
       • capacity
     • optical
       • cd
       • dvd
     • magnetic
       • tape
       • hdd
     • solid state
       • ssd
       • usb stick
   • it is needed because primary storage is not fast enough to keep up with the proceser

2. primary storage

   • why is it needed ?
     • to store all of the files that you have saved or downloaded
   • virtual memory
     • This type of memory is for when the computer runs out of available RAM and so uses part of the HDD (Hard Disk Drive) instead. This is not desirable however as the HDD is slower than just using RAM.
   • ram
     • (Random Access Memory) is a device that can plug into the motherboard. RAM contains programs, instructions and data that are currently being worked on (in use)
   • rom
     • bootstrap loader
       • Responsible for loading the Operating System into memory
     • (Read Only Memory) is usually a flash memory chip on the motherboard that contains instructions needed to start up (boot) the operating system
   • flash memory
     • This type of memory is solid state (i.e. No moving parts) that retains data even when power is removed. It is used in SSDs and memory cards, for example.
   • Sometimes called Main Memory. Refers to the memory areas that the CPU can access very quickly (Cache, RAM and ROM). Primary storage has the fastest read/write speeds and is mostly volatile.