By Andrew


People often get confused between main memory and backing storage, they are not the

same. Main memory is located inside the computer system. It can either be RAM or

ROM. Backing storage is outside the main processor, e.g. Hard Drives, CD/DVD drives,

USB Flash Memory (Pen Drives).


ROM is used to store a small part of the operating system called the bootstrap loader.

Data is stored permanently in ROM, Data is not lost when the power goes off, Data in ROM cannot be changed.


This is where the operating system is stored; it also holds all programs and data. You can

purchase additional RAM chips and install them in your desktopcomputer, which normally speeds up multi-tasking.The processor can write to and read from RAM at high speed.Data held in RAM can be changed, All data in RAM is lost when the power is switched off.