NoobToProLearner

Memory Hierarchy In contemporary usage, memory usually refers to random access memory, typically DRAM (Dynamic RAM) but memory can also refer to other forms of data storage. In computer terminology, the term storage refers to storage devices that are not directly accessible by the CPU (secondary or tertiary storage). Examples of secondary storage include hard disk drives, optical disc drives, and other devices that are slower than RAM but are used to store data permanently. These days, computers use different types of memory which can be organized in a hierarchy around the CPU, as a trade-off between performance and cost. The memory at a higher level in the storage hierarchy has less capacity to store data, is more expensive, and is fastest to access .