System Memory

System Memory

1. RAM

   • Random Access Memory
   • Is a temporary, volatile memory which stores data and programs you are currently working on e.g. Powerpoints, Excel Files
   • Two Types of RAM
     • SRAM
       • Static RAM is a type of memory which retains bits of data in its memory as long as power is being supplied. It does not have to be periodically refreshed.
     • DRAM
       • Dynamic RAM is a type of memory that is typically used for data or program coding that a computer processor needs to function properly. It has to refresh periodically.

2. ROM

   • Read Only Memory
   • Is a constant, non-volatile memory which contains instructions that boots the computer up.
   • Contains BIOS (Basic Input/Output System), a type of Firmware (Permanent Software embedded into ROM) which contains instructions to start up the computer; contains all the code required to control the hardware e.g. Keyboard, Monitor, Mouse.

3. Virtual Memory

   • An area of secondary storage that is used like RAM; Is temporary storage and is located on the hard disk
   • Created when a computer is running many processes at once and RAM is running low on space.
   • Works by having the Operating System (The software that runs a computer) make a part of the storage drive available to use as RAM. Then it copies data and moves it towards the hard disk; stores processes that are not immediately needed
   • Slows the computer down though because copying to a hard disk takes much longer than reading and writing to RAM.
   • Also much slower than Main Memory because processing power is being taken up by moving data around