1.2 Memory

1.2 Memory

1. CPU

   • Central Processing unit

2. RAM

   • Random Access Memory

3. Volatile

   • Gets emptied when the power is turned off

4. ROM

   • Read Only Memory
   • Stores boot sequence. This should never be changed.

5. Firmware

   • Permanent software programmed into ROM

6. Non - Volatile

   • Dosent lose the data when the device is turned off.

7. BIOS

   • Basic Input/Output system. Contains programs to load the hardware.

8. Disk Thrashing

   • When a computers virtual memory subsystem is in a constant state of paging.

9. Hard disk

   • Magnetic storage device

10. Portable

    • Can take it with you. Easily transportable

11. Internal

    • Inside

12. External

    • Outside

13. Flash memory

    • USB memory stick

14. Secondary Storage

    • Hardware that stores data other than RAM or ROM

15. Virtual memory

    • Virtual memory is simply and area of secondary storage that is used like RAM
    • Located on the Hard disk

16. Secondary Storage

    • RAM
      • Cache memory
        • CPU

17. Static RAM

    • Uses 5 transistors which are wired together to represent each bit. No need to be refreshed. More wiring per bit.

18. Dynamic RAM

    • Contains 1 transistor and capacitor that hold charge briefly. This needs to be reshreshed every few milliseconds

19. Primary memory.

    • Memory used to store data and instructions that are required by the CPU

20. Bootstrap loader

    • A small program that loads the operating system. Once the operating system is leaded it takes care of the rest

21. Flash memory

    • Electrons are forced into a layer between two barriers which hold the charge by using a hifh electric current

22. Reliable

    • How well it keeps your data intact.

23. Durability

    • Does the device break easily?
      • e.g if you drop it

24. Characteristics of RAM and ROM

    • RAM
      • Volatile
        • Holds instructions / programmes currently in use by the CPU
    • ROM
      • non-volatile
        • Stores the boot sequence

25. Sean Bentley

26. Solid State Drive (SSD)

    • Storage Device. No moving parts