1.2 Memory & 1.3 Storage

Description

Mind Map on 1.2 Memory & 1.3 Storage, created by Jamie Sparks on 10/05/2017.
Jamie Sparks
Mind Map by Jamie Sparks, updated more than 1 year ago
Jamie Sparks
Created by Jamie Sparks about 7 years ago
11
0

Resource summary

1.2 Memory & 1.3 Storage
  1. 1.2 Memory
    1. RAM contains programs, instructions and data that are currently being worked on (in use). RAM is volatile meaning that when the power is removed then all data is lost.
      1. ROM (Read Only Memory) is usually a flash memory chip on the motherboard that contains instructions needed to start up (boot) the operating system. ROM is non-volatile meaning that when power is removed, data is retained on the chip.
        1. The ROM chip in a PC is usually called BIOS
        2. Flash memory refers to memory that is solid state (i.e. No moving parts) that retains data even when power is removed.
          1. Virtual 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 much slower than RAM
          2. 1.3 Storage
            1. Primary Storage (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.
              1. Secondary Storage is non-volatile – it’s where all data (operating systems, applications and user files) are stored when not in use (e.g. HDD, USB Flash drive, SD card). Read/write speeds are much slower compared to primary storage.
                1. Types of storage
                  1. Optical
                    1. CD (700MB), DVD(4.7GB), Blu-Ray(25GB)
                      1. Cheap per GB and portable. Can even be given away on magazines!
                        1. Prone to getting scratched (not durable) and is slower than magnetic or solid state
                          1. Use is declining
                          2. Magnetic
                            1. High capacity and reliable. HDDs are generally around 2TB at the moment
                              1. Portable versions of HDDs are useful for backing up and transporting large amounts of data
                                1. Sensitive to being dropped (i.e not durable)
                                2. Solid State
                                  1. No moving parts (only uses memory chips, no spinning motors that are noisy/generate heat)
                                    1. Fast, reliable and highly portable (light and small).
                                      1. SD cards and USB Pen drives aren’t nearly as fast as SSDs, but still are very useful!

                                  Media attachments

                                  Show full summary Hide full summary

                                  Similar

                                  Atoms and Reactions
                                  siobhan.quirk
                                  AS Pure Core 1 Maths (AQA)
                                  jamesmikecampbell
                                  Databases
                                  Dean Whittle
                                  Of Mice and Men
                                  amyk4321
                                  GCSE History: The 2014 Source Paper
                                  James McConnell
                                  A level Computing Quiz
                                  Zacchaeus Snape
                                  GCSE Mathematics Topics
                                  goldsmith.elisa
                                  Maths Revision
                                  Asmaa Ali
                                  Lesson Planning: 4 Organisational Tips for Teachers
                                  miminoma
                                  1PR101 2.test - Část 4.
                                  Nikola Truong
                                  GENERAL PRACTICE-1
                                  Luis Felipe Chávez Choque