GCSE Computer Science/Memory

Main Memory

Specification link Show understanding of the difference between: primary, secondary and off-line storage and provide examples of each - 2016 CIE Syllabus p13

Main memory - data store that can be directly addressed by the CPU

Main memory is used to store program instruction and data, using the System Bus to communicate with CPU. Main memory is often created using Random Access Memory (or RAM) or Read Only Memory (ROM). Modern computers will have gigabytes of RAM, meaning that large programs can run and multiple programs can run at once. The more main memory that you have the larger the number of programs you can run at once.

Main memory is often made up of RAM modules, where you can adjust the amount by swapping in higher capacity modules or adding more modules