memory

primary memory

primary memory can be directly accessed by processor, is low latency and fixed within the computer case

ROM

read only memory - memory that is permanent and non volatile. it is known as firmware and hardware - it is not often changed and often soldered in place.

ROM embedded systems

in embedded systems it is big and it holds factory settings, set routines and start up routine

ROM general purpose computers

loads OS intro RAM, bootstrap loader which holds the start up instructions - BIOS, POST

RAM

volatile temporary memory. stores data and instructions currently in use - general purpose. in embedded - holds user input for processing

secondary storage

non volatile storage data which are copied into the computer memory before they are executed. It is not directly accessible by the processor and contents are transferred to RAM before processor. Fixed in computer casing, long term storage area with slower access speed